Question

If f(x) = x³ - 2, find f(3). 25 24 26 20

Answer 1

`A.) 25`

Explanation:

`f(3)` means that the value of x is 3. Insert this into the equation for x, but DO NOT insert the value into f(x). To not get confused, remember that f(x) is basically y. You can insert y into the equation to not get mixed up:

`f(x)=(3)^3-2\\\\or\\\\y=3^3-2`

Now simplify the equation, starting with exponents (PEMDAS):

`x^3=x*x*x\\\\3*3*3\\\\9*3=27\\\\f(x)=27-2\\\\or\\\\y=27-2`

Simplify subtraction:

`27-2=25\\\\f(x)=25\\\\or\\\\y=25`

:Done