Question

F(x)=-x³+2x²-11; f(-3)

Answer 1

`\text{f}(-3)=34`

Explanation:

Given cubic function:

`\text{f}(x)=-x^3+2x^2-11`

To find f(-3) substitute x = -3 into the given function:

`\begin{aligned}\implies \text{f}(-3) & =-(-3)^3+2(-3)^2-11\\& =-(-3 \cdot -3 \cdot -3)+2(-3 \cdot -3)-11\\& = -(-27)+2(9)-11\\& = 27+18-11\\& = 45-11\\& = 34\end{aligned}`

Answer 2

34

Explanation:

f(-3) = - (-3)³ + 2 × (-3)² - 11

= - (-27) + (2× 9) - 11

= 27 + 18 - 11

= 34