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Hello! I need some assistance with this homework question, pleaseQ2

Hello! I need some assistance with this homework question, pleaseQ2-example-1
User Daniel Rusev
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1 Answer

15 votes
15 votes

Recall that:


(f\cdot g)(x)=f(x)g(x)\text{.}

Then, if:


\begin{gathered} x\in\text{Dom(f)}\cap Dom(g) \\ \text{then} \\ x\in\text{Dom(f}\cdot g)\text{.} \end{gathered}

Now, notice that:


\begin{gathered} x\in\text{Dom(f}\cdot g)\text{ if } \\ f(x)\text{ and g(x) exists,} \\ \text{then} \\ x\in\text{Dom(f)}\cap Dom(g). \end{gathered}

Therefore:


\text{Dom(f}\cdot g)=\text{Dom(f)}\cap Dom(g).

Answer: True.

User Dhouty
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