Step-by-step explanation:
you mean the slope of the line between (8, 9) and (23, 9).
we can see that right away, as the y value does not change. it means it is a flat line, and that means the slope is 0.
now, formally :
the slope of a line is (y coordinate change / x coordinate change) when going from one point on the line to another.
the direction does not matter, but once we pick one for the comparison of one coordinate, we have to use the same direction also for the other.
I prefer to go from left to right.
so, from (8, 9) to (23, 9).
x changes by +15 (from 8 to 23).
y changes by 0 (from 9 to 9).
the slope is therefore 0/+15 = 0.
A 78.0 kg sprinter starts a race with an acceleration of 1.64 m/s2. If the sprinter accelerates at that rate for 25 m, and then maintains that velocity for the remainder of the 100 m dash, what will be his time (in s) for the race?
The sprinter will complete the race in approximately 17.07 seconds.
To calculate the time for the race, we need to consider two parts: the acceleration phase and the constant velocity phase.
Acceleration Phase:
The acceleration of the sprinter is 1.64 m/s², and the distance covered during this phase is 25 m. We can use the equation of motion to calculate the time taken during acceleration:
v = u + at
Here:
v = final velocity (which is the velocity at the end of the acceleration phase)
u = initial velocity (which is 0 since the sprinter starts from rest)
a = acceleration
t = time
Rearranging the equation, we have:
t = (v - u) / a
Since the sprinter starts from rest, the initial velocity (u) is 0. Therefore:
t = v / a
Plugging in the values, we get:
t = 25 m / 1.64 m/s²
Constant Velocity Phase:
Once the sprinter reaches the end of the acceleration phase, the velocity remains constant. The remaining distance to be covered is 100 m - 25 m = 75 m. We can calculate the time taken during this phase using the formula:
t = d / v
Here:
d = distance
v = velocity
Plugging in the values, we get:
t = 75 m / (v)
Since the velocity remains constant, we can use the final velocity from the acceleration phase.
Now, let's calculate the time for each phase and sum them up to get the total race time:
Acceleration Phase:
t1 = 25 m / 1.64 m/s²
Constant Velocity Phase:
t2 = 75 m / v
Total race time:
Total time = t1 + t2
Let's calculate the values:
t1 = 25 m / 1.64 m/s² = 15.24 s (rounded to two decimal places)
Now, we need to calculate the final velocity (v) at the end of the acceleration phase. We can use the formula:
v = u + at
Here:
u = initial velocity (0 m/s)
a = acceleration (1.64 m/s²)
t = time (25 m)
Plugging in the values, we get:
v = 0 m/s + (1.64 m/s²)(25 m) = 41 m/s
Now, let's calculate the time for the constant velocity phase:
t2 = 75 m / 41 m/s ≈ 1.83 s (rounded to two decimal places)
Finally, let's calculate the total race time:
Total time = t1 + t2 = 15.24 s + 1.83 s ≈ 17.07 s (rounded to two decimal places)
Therefore, the sprinter will complete the race in approximately 17.07 seconds.
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You sailed 0.055 units to the left and found treasure at 0.085 units find where the ship started
The ship started at the Position 0.14 units.
To determine the starting position of the ship, we can consider the distance sailed to the left and the distance to the treasure.
Given that you sailed 0.055 units to the left and found the treasure at 0.085 units, we can represent this situation mathematically as follows:
Starting position + Distance sailed to the left = Distance to the treasure
Let's assign a variable, "x," to represent the starting position of the ship.
The equation becomes:
x - 0.055 = 0.085
To find the value of x, we can solve this equation by isolating x on one side:
x = 0.085 + 0.055
x = 0.14
Therefore, the ship started at the position 0.14 units.
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"What scale of measurement is being used when a teacher measures the number of correct answers on a quiz for each student
Answer:
"Ratio " seems to be the appropriate choice.
Step-by-step explanation:
A scale that is being used to mark quantities with a regular process or order, a quantifiable significance discrepancy, as well as a "true zero" value. Any factors that should be considered on something like a ratio scale which can be calculated usually involve:Height: Should be represented in inches, centimeters, feet, respectively., and therefore can't be smaller than 0 (zero).
Consider the function below. (If an answer does not exist, enter DNE.) f(x) = x3 − 27x + 3 (a) Find the interval of increase. (Enter your answer using interval notation.)
Answer:
(-∞,-3) and (3,∞)
Step-by-step explanation:
f(x) = x³ − 27x + 3
1. Find the critical points
(a) Calculate the first derivative of the function.
f'(x) = 3x² -27
(b) Factor the first derivative
f'(x)= 3(x² - 9) = 3(x + 3) (x - 3)
(c) Find the zeros
3(x + 3) (x - 3) = 0
x + 3 = 0 x - 3 = 0
x = -3 x = 3
The critical points are at x = -3 and x = 3.
2. Find the local extrema
(a) x = -3
f(x) = x³ − 27x + 3 = (-3)³ - 27(-3) + 3 = -27 +81 + 3 = 57
(b) x = 3
f(x) = x³ − 27x + 3 = 3³ - 27(3) + 3 = 27 - 81 + 3 = -51
The local extrema are at (-3,57) and (3,-51).
3, Identify the local extrema as maxima or minima
Test the first derivative (the slope) over the intervals (-∞, -3), (-3,3), (3,∞)
f'(-4) = 3x² -27 = 3(4)² - 27 = 21
f'(0) = 3(0)² -27 = -27
f'(4) = 3(4)² - 27 = 51
The function is increasing on the intervals (-∞,-3) and (3,∞).
The graph below shows the critical points of your function.
aleks math please answer
The slope of the lines
Line 1 = -5/2
Line 2 = -5/4
Line 3 = -5/4
Line 1 and 2 are neither
Line 1 and 3 are neither
Line 2 and 3 are parallel
What is slope?Slope can be defined as the degree of steepness of a line.
The formula for calculating the slope of a line is expressed as;
Slope, m = y₂ - y₁/x₂ - x₁
Given that the line coordinates are;
(x₁, y₁)(x₂ , y₂)
For Line 1, we have;
(0, 7)(8 , -3)
Substitute the values, we get;
Slope, m = (-3 - 7)/(8 - 0)
subtract the values
Slope, m = -10/8 = -5/2
For line 2
(8, -8)(4, -3)
Substitute the values
Slope, m = -3 -(-8)/4 - 8
Slope, m = -5/-4 = 5/4
For Line 3
(-4, 3)(4, -7)
Substitute the values
Slope, m = -7 - (3)/4 -(-4)
Slope, m = -10/8 = -5/4
Note that, lines with the same slope are parallel and if the slope of one line is the negative reciprocal of the second line, then they are perpendicular.
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A room has 32 people, and 3/4 of them are wearing blue jeans. What fraction of people in the room are wearing blue jeans, using 32 as the denominator?
Answer:
24/32
Step-by-step explanation:
Cells B1, C1, and D1 contain the values Seat1Row1, Seat2Row1, and Seat3Row1. If cells B1, C1, and D1 were selected, and autofill
used to fill E1, F1, and G1, what would be the auto-filled values?
Seat1Row2, Seat2Row2, Seat3Row2
Seat 2Row2, Seat3Row3, Seat4Row4
Seat 1Row1, Seat2Row2, Seat3Row2
Seat 2Row2, Seat3Row2, Seat4Row2
In the event that cells B1, C1, and D1 were highlighted and then used to fill E1, F1, and G1, the values we would see are A. Seat1Row2, Seat2Row2, Seat3Row2.
What values would be in E1, F1, and G1?When using a spreadsheet, you can autofill succeeding cells if you highlight the preceding ones and then drag the cursor.
If Seat1Row1, Seat2Row1, and Seat3Row1 are in the cells B1, C1, and D1, then the spreadsheet would take note of the "1s" at the end of the values.
When it is then used to autofill the next cells, it would make this a 2 such that we see Seat1Row2, Seat2Row2, Seat3Row2.
If cells H1, I1, and J1 are filled, we would then see Seat1Row3, Seat2Row3, Seat3Row3.
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PLEASE HELP DUE ASAP!
The graph of the function f(x) = 3√(3 - x) is at the end of the answer.
How to graph the function?We want to graph the function f(x) = 3√(3 - x)
To do so, we need to find some points on that line, to find the points we need to evaluate the function in some values of x
if x = -1
f(-1) = 3√(3 + 1) = 3*2 = 6
if x = 3
f(3) = 3√(3 - 3) = 3*0 = 0
if x = -6
f(-6) = 3*√(3 + 6) = 3*3 = 9
if x = -13
f(-13) = 3*√(3 + 13) = 3*4 = 12
Then the points are (-1, 6), (3, 0), (-6, 9), (-13, 12)
Now we can just graph these 4 points and connect them with a curve, the graph of the function is below.
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Each of 6 students reported the number of movies they saw in the past year. Here is what they reported. 14, 11, 15, 19, 12, 10 Send data to calculator Find the mean number of movies that the students saw. If necessary, round your answer to the nearest tenth. movies X Ś
The mean number of movies that the students saw is 13.5 (rounded to the nearest tenth).
To find the mean number of movies the students saw, you need to calculate the average of the given data. Here are the reported numbers of movies seen by the 6 students: 14, 11, 15, 19, 12, 10.
To calculate the mean, you sum up all the reported numbers and divide by the total number of students. In this case, the total number of students is 6.
So, let's calculate the mean:
(14 + 11 + 15 + 19 + 12 + 10) / 6 = 81 / 6 = 13.5
Therefore, the mean number of movies that the students saw is 13.5 (rounded to the nearest tenth).
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Kai wrote the number 85 on the board. Is 85 a prime or composite?
Hello there!
85 is composite.
There are 3 ways of determining whether a number is prime or composite.
Check if the number is even. If it is, it's 100% compositeIf the number is odd, then look at its last digit. If it's 2, 4, 6, 8, 0 or 5, then it is composite.If the last digit is not 2, 4, 6, 8, 0 or 5, look at the factors of the given number. If it has 2 factors, then it's prime. If it has more than 2 factors, it's composite.Hope this helps!
\(GraceRosalia\)
what situation can be modeled using the same equation -4 + 4 equals 0
Today we will focus on solving word problems with systems of equations. Read the following word problem.
Today’s cafeteria specials are a turkey sandwich and a pepperoni pizza. During 1st lunch, the cafeteria sold 70 turkey sandwiches and 29 pepperoni pizzas for a total of $367. During 2nd lunch, 70 turkey sandwiches and 45 pepperoni pizzas were sold for a total of $415. How much does each item cost?
How would you solve the word problem? Why would you choose that method to solve it? What is the solution?
Write at least two sentences about how you solved this problem. You can think about a new method of solving or use methods you already have learned. Also, write at least one sentence on what the solution means for the problem.
Answer:
The pepperoni pizzas cost $3.00 each.
The cost of the turkey sandwich is $4.00
Step-by-step explanation:
Let t = the number of turkey sandwiches
Let p = the number of pepperoni pizzas.
I choose to use elimination to solve.
70t + 29 p = 367 ⇒ x (-1) ⇒ -70t - 29p = -367
70t + 45p = 415 ⇒ (+) 70t + 45p = 415
16p = 48 Divide both sides by 16
p = 3
The pepperoni pizzas cost $3.00 each.
Take either of the two original equation and substitute 3 for p and solve for t.
70t + 29p = 367
70t + 29(3) = 367
70t + 87 = 367 Subtract 87 from both sides
70t + 87 - 87 = 367 - 87
70t = 280 Divide both sides by 70
t = 4
The cost of the turkey sandwich is $4.00
Check:
70t + 29p = 367
70(4) + 29(3) = 367
280 + 87 = 367
367 = 367 checks
70t + 45p = 415
70(4) + 45(3) = 415
280 + 135 = 415
415 = 415 checks
Helping in the name of Jesus.
In a recent survey of 36 people, 18 said that their favorite color of car was blue.
What percent of the people surveyed liked blue cars? Explain your answer with every step you took to get to it.
Answer: The percentage of people surveyed who liked blue cars is 50%.
Step-by-step explanation:
Total number of people partaking in survey= 36
number of people who like blue cars= 18
therefore, fraction of people who liked blue cars= \(\frac{18}{36}\)
hence, percentage of people who liked blue cars= (18/36)*100 %
= 50%
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Answer:
Percentage of people who like blue-coloured cars is 50%
Number of people who were surveyed=36
Number of people who like blue-colored cars=18
Therefore, Percentage of people who like blue cars= (Number of people who like blue cars/ Number of people who were surveyed)*100
=(18/36)*100
=50%
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The rectangle has an area of x^2-9 square meters and a width of x-3 meters
It is known that a
a) add 4 to both sides of the inequality
b) multiply each side of the inequality by 8
PLEASE HELP NEED ASAPPPP WILL GIVE BRAINLIEST TO FIRST CORRECT ANSWER
Answer:
the answer is B
Step-by-step explanation:
Multiplying or dividing both sides by a negative number reverses the inequality. This means < changes to >, and vice versa. For example, given that 5 < 8 we can multiply both sides by 6 to obtain 30 < 48 which is still true. −30 > −48, which is a true statement.
when solving inequalities with absolute values When solving an inequality: • you can add the same quantity to each side • you can subtract the same quantity from each side • you can multiply or divide each side by the same positive quantity If you multiply or divide each side by a negative quantity, the inequality symbol must be reversed.
It is estimated that approximately 8.26% Americans are afflicted with diabetes. Suppose that a certain diagnostic evaluation for diabetes will correctly diagnose 94.5% of all adults over 40 with diabetes as having the disease and incorrectly diagnoses 3.5% of all adults over 40 without diabetes as having the disease. a) Find the probability that a randomly selected adult over 40 does not have diabetes, and is diagnosed as having diabetes (such diagnoses are called "false positives").
Answer:
0.032109
Step-by-step explanation:
From the given information
the estimate of those afflicted with diabetes = 0.0826
the estimate of those that are not afflicted with diabetes = 1 - 0.0826
= 0.9174
From adult with 40
Pr (correct diagnoses) = 0.945
Pr(incorrect diagnoses) = 0.035
The objective that the probability of a randomly selected adult which is over 40 and does not have diabetes, and is diagnosed as having diabetes (false positive) is = 0.9174 × 0.035
= 0.032109
FInd the measure of the arc using the picture provided , please and thanks
The measure of arc angle QTP is 204 degrees.
How to find arc angle?When a tangent and a secant intersect outside a circle then the measure of the angle formed is one-half the positive difference of the measures of the intercepted arcs.
Therefore, let's find the measure of arc angle QTP as follows:
90 = 0.5(x - 68)
90 = 0.5x - 34
0.5x = 124
x = 124 / 0.5
x = 248 degrees
Where
x = arc angle TSQ
Therefore,
arc QP = 44 degrees
Therefore,
arc QTP = 248 - 44
arc QTP = 204 degrees
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a four sided ploygon is called?
Answer:
square, or cube
Step-by-step explanation:
Answer:
quadrilateral
Step-by-step explanation:
What is the expected price of a calculator in the year 2000 if it costs $19.12 in 2015? You can use the chart below for a reference of CPI values. Year CPI 1990 130.7 1995 152.4 2000 172.2 2005 195.3 2010 218.056 2015 237.017
Answer:
43w6
Step-by-step explanation:
I'm not going anywhere and I'm not sure what to say what
1. Last year 90 students signed up for a summer trip to Washington, D.C. This year 55 students have
signed up. What is the percent decrease in the number of students going on the trip?
Answer:
The decrease in the number of students going on the trip is 38.8889% or 38.89% rounded to the nearest hundredth.
find the solution of 2b + 1/2 = 3 if the replacement set is (1/2 , 3/4 , 1 , 5/4 , 3/2 , 7/2)
Answer:
b = 5/4
Step-by-step explanation:
We need to find the solution of the following equation :
\(2b+\dfrac{1}{2}=3\)
Subtracting 1/2 both sides we get :
\(2b+\dfrac{1}{2}-\dfrac{1}{2}=3-\dfrac{1}{2}\\\\2b=\dfrac{5}{2}\)
Dividing both sides by 2 we get :
\(b=\dfrac{5}{4}\)
so, the value of b is 5/4.
likes to collect records. Last year had 10 records in collection. Now has 14 records. What is the percent increase of collection?
The percent increase in the collections is 40%.
What is the percent increase?Percentage is the fraction of an amount that is usually expressed as a number out of hundred. The sign that is used to represent percentage is %.
Percent increase = (increase in the number of collections / initial collections) x 100
Increase in collections = 14 - 10 = 4
= (4/10) x 100 = 40%
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is -81,572 ratonal or irrational
Answer:
rational
Step-by-step explanation:
as it is of the form p/q
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Here's a graph of a linear function. Write the
equation that describes that function.
xpress it in slope-intercept form.
Answer:
the slope intercept form is y = (1/2)x - 1
Step-by-step explanation:
The slope-intercept form is, y = mx + b
We see from looking at the graph that,
at x = 0, y = -1
So, from this we find that b = -1
at x = 2, y = 0,
now, we find the slope m,
using,
\(m = \frac{y_{2} -y_1}{x_2-x_1}\)
Using x_2 = 2, y_2 = 0,
x_1 = 0, y_1 = -1, we get,
m = (0-(-1))/(2-0)
m = 1/2
So, the slope intercept form is,
y = (1/2)x - 1
Andy saved $80 over the summer from his part-time job. He withdrew 30% of the money to buy new clothes. How much money does Andy have left in
the account after withdrawing the money?
Answer:
$56 I think
Step-by-step explanation:
because 30% of 80 is 24 and 80-24=56
A) Find an equation for the line perpendicular to the tangent line to the curve y=x^3-4x+6 at the point (2,6)
-The equation is y=
b) What is the smallest slope on the curve? At what point on the curve does the curve have this slope?
-The smallest slope on the curve is
-The curve has the smallest slope at the point
c) Find equations for the tangent lines to the curve at the points where the slope of the curve is 8.
Answer:
f(x) = x³ - 4x + 6
f'(x) = 3x² - 4
a) f'(2) = 3(2²) - 4 = 12 - 4 = 8
6 = 8(2) + b
6 = 16 + b
b = -10
y = 8x - 10
b) 3x² - 4 = 0
3x² = 4, so x = ±2/√3 = ±(2/3)√3
= ±1.1547
f(-(2/3)√3) = 9.0792
f((2/3)√3) = 2.9208
c) 3x² - 4 = 8
3x² = 12
x² = 4, so x = ±2
f(-2) = (-2)³ - 4(-2) + 6 = -8 + 8 + 6 = 6
6 = -2(8) + b
6 = -16 + b
b = 22
y = 8x + 22
f(2) = 6
y = 8x - 10
The equation perpendicular to the tangent is y = -1/8x + 25/4
-The smallest slope on the curve is 2.92
The curve has the smallest slope at the point (1.15, 2.92)
The equations at tangent points are y = 8x + 16 and y = 8x - 16
Finding the equation perpendicular to the tangentFrom the question, we have the following parameters that can be used in our computation:
y = x³ - 4x + 6
Differentiate
So, we have
f'(x) = 3x² - 4
The point is (2, 6)
So, we have
f'(2) = 3(2)² - 4
f'(2) = 8
The slope of the perpendicular line is
Slope = -1/8
So, we have
y = -1/8(x - 2) + 6
y = -1/8x + 25/4
The smallest slope on the curveWe have
f'(x) = 3x² - 4
Set to 0
3x² - 4 = 0
Solve for x
x = √[4/3]
x = 1.15
So, we have
Smallest slope = (√[4/3])³ - 4(√[4/3]) + 6
Smallest slope = 2.92
So, the smallest slope is 2.92 at (1.15, 2.92)
The equation of the tangent lineHere, we set f'(x) to 8
3x² - 4 = 8
Solve for x
x = ±2
Calculate y at x = ±2
y = (-2)³ - 4(-2) + 6 = 6: (-2, 0)
y = (2)³ - 4(2) + 6 = 6: (2, 0)
The equations at these points are
y = 8x + 16
y = 8x - 16
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Write the standard form equation for an
ellipse with vertices: (4, 10) and (-12, 10)
and foci: (2, 10) and (-10, 10)
Check the picture below, so the ellipse looks more or less like so
\(\textit{ellipse, horizontal major axis} \\\\ \cfrac{(x- h)^2}{ a^2}+\cfrac{(y- k)^2}{ b^2}=1 \qquad \begin{cases} center\ ( h, k)\\ vertices\ ( h\pm a, k)\\ c=\textit{distance from}\\ \qquad \textit{center to foci}\\ \qquad \sqrt{ a ^2- b ^2} \end{cases} \\\\[-0.35em] ~\dotfill\)
\(\begin{cases} h=-4\\ k=10\\ a=8 \end{cases}\implies \cfrac{(x- (-4))^2}{ 8^2}+\cfrac{(y- 10)^2}{ b^2}=1\implies \cfrac{(x+4)^2}{ 8^2}+\cfrac{(y- 10)^2}{ b^2}=1 \\\\\\ \stackrel{\textit{we know that c = 6}}{6=\sqrt{8^2 - b^2}}\implies 6^2=8^2-b^2\implies b^2=8^2-6^2\implies \underline{b^2=28} \\\\\\ \cfrac{(x+4)^2}{ 8^2}+\cfrac{(y- 10)^2}{ b^2}=1\implies {\Large \begin{array}{llll} \cfrac{(x+4)^2}{ 64}+\cfrac{(y- 10)^2}{ 28}=1 \end{array}}\)
An election ballot asks voters to select six city commissioners from a group of 24 candidates in how many ways can this be done? Six city commissioners can be selected from a group of 24 candidates in blank different ways
Answer:
134,596 diffrent ways.
Step-by-step explanation:
Combination has to do with selection. When n object is to be selected from n objects, this can be achieved using the combination formula as shown; \
nCr = n!/(n-r)!r!
If an election ballot asks voters to select six city commissioners from a group of 24 candidates, then the selection can be done in 24C6 different ways.
Applying the formula above:
24C6 = 24!/(24-6)!6!
24C6 = 24!/18!6!
24C6 = 24*23*22*21*20*19*18!/18!*6*5*4*3*2
24C6 = 24*23*22*21*20*19/24*30
24C6 = 23*22*21*20*19/30
24C6 = 134,596 different ways.
Hence, Six city commissioners can be selected from a group of 24 candidates in 134,596 different ways
The hexagonal prism below has a height of 9 units and a volume of 216.9 units. Find the area of one of its bases.
Answer:
The answer is 24.1 unit²
Step-by-step explanation:
Volume of prisms=cross sectional area×h
cross sectional area=Volume of prisms/height
A=216.9/9
A=24.1 unit²
A particle in the ocean moves with a wave. The motion of the particle can be modeled by the cosine function. If a 14 in. wave occurs every 10 s, write a function that models the height of the particle in inches y as it moves in seconds x. What is the period of the function?
The required function y = 7 cos (2π * 0.1 * x) and period of the function is 10 seconds, which is the time it takes for one complete cycle of the wave.
How to find the cosine function of this problem?he cosine function can be used to model periodic motion, and its general form is:
y = A cos (Bx + C) + D
where A is the amplitude, B is the frequency, C is the phase shift, and D is the vertical shift.
In this case, we know that a 14 in. wave occurs every 10 s, so we can use this information to find the frequency, which is the reciprocal of the period. The period is the time it takes for one complete cycle of the wave, which in this case is 10 s.
Therefore, the frequency is:
\(f = \frac{1}{T}=\frac{1}{10} = 0.1 Hz\)
We can also see that the amplitude of the wave is 7 inches, since the wave has a height of 14 inches from its highest point to its lowest point.
Now we can write the function that models the height of the particle in inches y as it moves in seconds x:
y = 7 cos (2π * 0.1 * x)
Here, the frequency is expressed in radians per second (2π * 0.1 = 0.2π), since the cosine function takes radians as its argument. The phase shift and vertical shift are both zero in this case, since the wave starts at its highest point and has no vertical shift.
Therefore, the period of the function is 10 seconds, which is the time it takes for one complete cycle of the wave.
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