Question

if k(x) = 2x³ - 3√x then k (9) is

Answer 1

If they ask you for k (9), what you should do is replace at x = 9 in the function k (x) that they give you. Then

$\begin{gathered} k(x)=2x^3-3\sqrt[]{x} \\ k(9)=2(9)^3-3\sqrt[]{9} \\ k(9)=2\cdot729-3\cdot3 \\ k(9)=1458-9 \\ k(9)=1449 \end{gathered}$

Therefore, if k(x) = 2x³ - 3√x then k (9) is​ 1449.