Recall that to get the x-intercepts, we set the f(x) = y = 0, thus
![\bf \stackrel{f(x)}{0}=-4cos\left(x-\frac{\pi }{2} \right)\implies 0=cos\left(x-\frac{\pi }{2} \right) \\\\\\ cos^{-1}(0)=cos^{-1}\left[ cos\left(x-\frac{\pi }{2} \right) \right]\implies cos^{-1}(0)=x-\cfrac{\pi }{2} \\\\\\ x-\cfrac{\pi }{2}= \begin{cases} \frac{\pi }{2}\\\\ \frac{3\pi }{2} \end{cases}](https://tex.z-dn.net/?f=%5Cbf%20%5Cstackrel%7Bf%28x%29%7D%7B0%7D%3D-4cos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%5Cimplies%200%3Dcos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%0A%5C%5C%5C%5C%5C%5C%0Acos%5E%7B-1%7D%280%29%3Dcos%5E%7B-1%7D%5Cleft%5B%20cos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%20%5Cright%5D%5Cimplies%20cos%5E%7B-1%7D%280%29%3Dx-%5Ccfrac%7B%5Cpi%20%7D%7B2%7D%0A%5C%5C%5C%5C%5C%5C%0Ax-%5Ccfrac%7B%5Cpi%20%7D%7B2%7D%3D%0A%5Cbegin%7Bcases%7D%0A%5Cfrac%7B%5Cpi%20%7D%7B2%7D%5C%5C%5C%5C%0A%5Cfrac%7B3%5Cpi%20%7D%7B2%7D%0A%5Cend%7Bcases%7D)
Option B: 4 is the multiplicative rate of change of the function
Explanation:
The exponential growth function is 
We need to determine the multiplicative rate of change of the function.
First, let us determine the values of function.
x y
1 8
2 32
3 128
4 512
Since, the multiplicative rate of change of an exponential function is the number by which the next term is increasing or decreasing.
Thus, the multiplicative rate of change of the function is given by
Multiplicative rate of change of the function = 
Multiplicative rate of change of the function = 
Multiplicative rate of change of the function = 
Thus, the multiplicative rate of change of the function is 4
Therefore, Option B is the correct answer.
Answer:
2) 62.5 wpm
3) 12.7 miles per gallon
4)18 commercials per hour
5) 22.9 ounces per dollar
Step-by-step explanation:
2) 500 words / 8 minutes = 62.5 words per 1 minute
3) 216 miles / 17 gallons = 12.7 miles per gallon
4) 36 commercials / 2 hours = 18 commercials per hour
5) 64 oz / $2.79 = 22.9 oz per $1
9514 1404 393
Answer:
x = 10
Step-by-step explanation:
The marked sides are proportional, so we have ...
x/8 = (x +5)/12
3x = 2(x +5) . . . . . multiply by 24 to clear fractions
3x = 2x + 10 . . . . . eliminate parentheses
x = 10 . . . . . . . . . . subtract 2x
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<em>Alternate solution</em>
We observe that the difference between the upper segment lengths is ...
(x +5) -(x) = 5
and the difference between the lower segment lengths is ...
12 -8 = 4
This means the upper segment lengths are 5/4 times as long as the lower segments. Then ...
x = (5/4)(8) = 10