Question

I'm not understanding this equations I'm doing how I was taught but does answer still isn't right..so the math equation is f(x)=2x
`f{x} =2(x)^(3) - 3(x)^(2) + 7`f(-1)=

Answer 1

The given equation is

`f(x)=2x^3-3x^2+7`

We need to find f(-1)

That means substitute x by -1 in the given function

`f(-1)=2(-1)^3-3(-1)^2+7`

since (-1)^3 = -1 ------- (-1)(-1)(-1) = -1

Since (-1)^2 = 1 -------- (-1)(-1) = 1, then

`\begin{gathered} f(-1)=2(-1)-3(1)+7 \\ f(-1)=-2-3+7 \\ f(-1)=-5+7 \\ f(-1)=2 \end{gathered}`

Then f(-1) = 2