Question

Pls help (kinda easy)

A function is shown: f(x) = 4x2 − 1.

Choose the equivalent function that best shows the x-intercepts on the graph.

f(x) = (4x + 1)(4x − 1)
f(x) = (2x + 1)(2x − 1)
f(x) = 4(x2 + 1)
f(x) = 2(x2 − 1)

Answer 1

b

Explanation:

Answer 2

`f(x)=(2x+1)(2x-1)`.

Explanation:

We want to convert the function into the form that let's us easily find the x-intercept, and it would be for the form
`(ax+b)(cx+d)` because then we can find the x-intercept in the following manner:

`(ax+b)(cx+d)=0`

`x=-b/a`

`x=-d/c`

We factor our function
`f(x)=4x^2-1` and get

`\boxed{f(x)=(2x+1)(2x-1)}`

Now this form let's us easily find the x-intercepts:

`x=-1/2`

`x=1/2`

and so we pick the second choice: f(x)=(2x+1)(2x-1).