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Let $f:\mathbb{R}\rightarrow \mathbb{R}$ and $g:\mathbb{R}\rightarrow \mathbb{R}$ be continuous. Is $h:\mathbb{R}\rightarrow \mathbb{R}$, where $h(x): = f(x) \times g(x)$, still continuous?
I guess it is, but I feel difficult to manipulate the absolute difference:

$|h(x_2)-h(x_1)|=|f(x_2)g(x_2)-f(x_1)g(x_1)| \dots $

Thanks in advance!

1 Answers 1

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Hint:

$\left| f(x+h)g(x+h) - f(x)g(x) \right| = \left| f(x+h)\left( g(x+h) - g(x) \right) + \left( f(x+h) - f(x) \right) g(x) \right|$

Can you proceed from here?