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Simplify $-2\sin(x)\cos(x)-2\cos(x)$

The above expression is the derivative of a function, and part of a larger problem. I am wanting to simplify this to the form $-2(\sin(x)+1)\cos(x)$. I'm having trouble figuring out how to simplify this, even though I know where I am supposed to end up. Any help or hints would be appreciated.

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    $\begingroup$ Factor out $-2\cos(x)$ and you get the desired result. $\endgroup$ – Christian Ivicevic Nov 7 '15 at 18:37
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    $\begingroup$ If it is for a derivative of a function ,I prefer to rewrite it as $−2sin(x)cos(x)−2cos(x) =\\-sin(2x)-2cos(x)$ $\endgroup$ – Khosrotash Nov 7 '15 at 18:38
  • $\begingroup$ That's what I was looking for. Thanks to you both! $\endgroup$ – McB Nov 7 '15 at 18:39
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    $\begingroup$ There's something fishy here. Somebody is learning calculus, but they can't simplify $-2\sin(x)\cos(x)-2\cos(x)$ to $-2(\sin(x)+1)\cos(x)$? It doesn't make sense. $\endgroup$ – TonyK Nov 7 '15 at 18:43
  • $\begingroup$ It was simply dumb oversight on my part... Sorry! @TonyK $\endgroup$ – McB Nov 7 '15 at 18:44
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Hint: You have a common factor of $-2\cos(x)$ in both terms.

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