Question

Question 13 of 25
Find f(-2) for f(x) = 2(4)^x

Answer 1

the answer is A

Explanation:

put it in the calculator

Answer 2

`(1)/(8)`

Explanation:

When you have a negative exponent like
`((a)/(b))^(-x)` you simply take the reciprocal and then the denominator takes the exponent. So it becomes
`(b)/(a^(x))`.

So now you simply plug -2 as x. This gives you
`2(4)^(-2)`. and 4 is essentially
`(4)/(1)`. So it becomes
`(1)/(4^2)` which is
`(1)/(16)`. So multiplying it by 2 you get
`(2)/(16)`. Which can be written as
`(2)/(8 * 2)` so the 2's cancel out and the fraction becomes
`(1)/(8)`