Answer:
The answer is 81.
Step-by-step explanation:
Since the power of 4 is even, the result will be positive.

Simplify.

<u>hence</u><u>,</u><u> </u><u>the</u><u> </u><u>answer</u><u> </u><u>is</u><u> </u><u>Option</u><u> </u><u>A</u><u>)</u><u> </u><u>81</u><u>.</u>
We can use the fact that, for
,

Notice that
![\dfrac{\mathrm d}{\mathrm dx}\left[\dfrac1{1-x}\right]=\dfrac1{(1-x)^2}](https://tex.z-dn.net/?f=%5Cdfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dx%7D%5Cleft%5B%5Cdfrac1%7B1-x%7D%5Cright%5D%3D%5Cdfrac1%7B%281-x%29%5E2%7D)
so that
![f(x)=\displaystyle\frac5{(1-x)^2}=5\frac{\mathrm d}{\mathrm dx}\left[\sum_{n=0}^\infty x^n\right]](https://tex.z-dn.net/?f=f%28x%29%3D%5Cdisplaystyle%5Cfrac5%7B%281-x%29%5E2%7D%3D5%5Cfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dx%7D%5Cleft%5B%5Csum_%7Bn%3D0%7D%5E%5Cinfty%20x%5En%5Cright%5D)



By the ratio test, this series converges if

so the series has radius of convergence
.
60x1.15=69
Retail price is $69
The inequality is: x*0.75 + 3.00 < 20.00, where x represents the number of miles. When you solve the inequality, you get 22.66 miles. When you round up to 23 miles, you don't satisfy the inequality, so you have to round down to 22 miles.
Answer: (C) 22 miles
X = the square root of 29, or the square root of -29.