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Let f(x) = -2x + 7 and g(x) = -6x + 3. Find f.g and state its domain.Let f(x) = -2x + 7 and g(x) = -6x + 3. Find and state its domain.-14x2 + 36x - 18; all real numbers12x2 - 48x + 21; all real numbers-14x2 + 36x - 18; all real numbers except x = 712x2 - 48x + 21; all real numbers except x = 1

User James Trimble
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1 Answer

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14 votes

Step-by-step explanation:

We are given two functions:


\begin{gathered} f(x)=-2x+7 \\ g(x)=-6x+3 \end{gathered}

The question wants us to obtain f.g and its's domain

To do so,

Let us first obtain f.g


fg=f(x)* g(x)=\mleft(-2x+7\mright)*(-6x+3)=12x^2-48x+21

Next, we will find its domain

We can use the graph below to help

The domain of f.g is


\begin{bmatrix}\mathrm{Solution\colon}\: & \: -\infty\: Therefore[tex]\text{The domain is all real numbers}

Hence

The answer is the second option


12x^2-48x+21;\text{ All real numbers}

Let f(x) = -2x + 7 and g(x) = -6x + 3. Find f.g and state its domain.Let f(x) = -2x-example-1
User Evangelist
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