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F(x)=x^2-2 and g(x)=x^3+2(f•g)(-2)=

User Gavrie
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1 Answer

6 votes

Given the functions:


\begin{gathered} f\mleft(x\mright)=x^2-2 \\ \\ g\mleft(x\mright)=x^3+2 \end{gathered}

You need to multiply them in order to find:


(f\cdot g)(x)

Then, you get:


(f\cdot g)(x)=\mleft(x^2-2\mright)\mleft(x^3+2\mright)
(f\cdot g)(x)=(x^2)(x^3)+(x^2)(2)-(2)(x^3)-(2)(2)^{}
(f\cdot g)(x)=x^5+2x^2-2x^3-4
(f\cdot g)(x)=x^5-2x^3+2x^2-4

Substitute the following value of "x" into the function:


x=-2

And then evaluate, in order to find:


\mleft(f\cdot g\mright)\mleft(-2\mright)

Then, you get:


(f\cdot g)(-2)=(-2)^5-2(-2)^3+2(-2)^2-4
\begin{gathered} (f\cdot g)(-2)=(-2)^5-2(-2)^3+2(-2)^2-4 \\ \\ (f\cdot g)(-2)=-32-2(-8)^{}+2(4)^{}-4 \end{gathered}
(f\cdot g)(-2)=-32+16^{}+8^{}-4
(f\cdot g)(-2)=-12

Hence, the answer is:


(f\cdot g)(-2)=-12

User Amar Palsapure
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