O Graphs, Functions, and Systems
Evaluating functions: Linear and quadratic or cubic

The functions $f$ and $g$ are defined as follows.
$f (x) = - 5 x + 4 g (x) = 2 x^{3} + 6$

Find $f (4)$ and $g (- 3)$ .
Simplify your answers as much as possible.
$\begin{matrix} f (4) = \\ g (- 3) = \end{matrix}$

Answer

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Answer

So, the final answers are: $f (4) = - 16$ and $g (- 3) = - 48$ .

Steps

Step 1 ：The functions $f$ and $g$ are defined as follows: $f (x) = - 5 x + 4$ and $g (x) = 2 x^{3} + 6$ .

Step 2 ：To find the value of $f (4)$ , we substitute $x = 4$ into the function $f (x) = - 5 x + 4$ .

Step 3 ：After substituting, we get $f (4) = - 5 (4) + 4 = - 16$ .

Step 4 ：To find the value of $g (- 3)$ , we substitute $x = - 3$ into the function $g (x) = 2 x^{3} + 6$ .

Step 5 ：After substituting, we get $g (- 3) = 2 (- 3)^{3} + 6 = - 48$ .

Step 6 ：So, the final answers are: $f (4) = - 16$ and $g (- 3) = - 48$ .