Question

Find f(x) • g(x) if f(x) = x2 – 7 and g(x) = x2 + 3x + 7

Answer 1

Given the functions:

`\begin{gathered} f(x)=x^2-7 \\ g(x)=x^2+3x+7 \end{gathered}`

We will find: f(x) • g(x)

So, we will find the product of the functions

We will use the distributive property to get the result of the multiplications

So,

`\begin{gathered} f\mleft(x\mright)•g\mleft(x\mright)=(x^2-7)\cdot(x^2+3x+7) \\ f\mleft(x\mright)•g\mleft(x\mright)=x^2\cdot(x^2+3x+7)-7\cdot(x^2+3x+7) \\ f\mleft(x\mright)•g\mleft(x\mright)=x^4+3x^3+7x^2-7x^2-21x-49 \\ f\mleft(x\mright)•g\mleft(x\mright)=x^4+3x^3-21x-49 \end{gathered}`

so, the answer will be:

`f\mleft(x\mright)•g\mleft(x\mright)=x^4+3x^3-21x-49`