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Find functions of f and g are defined as followingsf(x)=4x^2-x g(x)=-2x-1

Find functions of f and g are defined as followingsf(x)=4x^2-x g(x)=-2x-1-example-1
User Sona Das
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1 Answer

8 votes
8 votes

We are asked to evaluate functions at specif values. We will start by the function:


f(x)=4x^2-x

We have to evaluate this function at x=-4, we do so, by substituting all the x's by the value -4 in the equation for f, as follows:


\begin{gathered} f(-4)=4(-4)^2-(-4) \\ \text{ }=4(16)+4 \\ \text{ = 64+}4 \\ \text{ =68} \end{gathered}

Therefore the answer for the first box is 68

Now we will do the second evaluation, this time we are asked to find g(6) where the function g is given by


g(x)=-2x-1

Substituting all the x by the value 6, we find


\begin{gathered} f(6)=-2(6)-1 \\ =-12-1 \\ =-13 \end{gathered}

Therefore, the answer for the second box is -13

User Purple Hexagon
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