Question

Find f (2b^2) for (x)=x^2-4x

Answer choice is
A. 4b^4 -8b^2
B. 2b^4-8b^2
C. -4b^2
D. 4b^2 - 8b^8

Answer 1

A

Explanation:

We are given the function:

`f(x) = x^2 - 4x`

And we want to find:

`\displaystyle f(2b^2)`

Substitute:

`\displaystyle f(2b^2) =(2b^2)^2 -4(2b^2)`

And evaluate:

`\displaystyle \begin{aligned} f(2b^2) &=(2b^2)^2 -4(2b^2) \\ &=(4b^4) +(-8b^2) \\ &= 4b^4 - 8b^2 \end{aligned}`

In conclusion, our answer is A.