To find the derivative of sin(2x). So far here is what I did:(adsbygoogle = window.adsbygoogle || []).push({});

lim h -> 0 (sin(2x+2h)-sin(2x))/h

= (sin2xcos2h+cos2xsin2h-sin2x)/h

= (2sinxcosx(cos2h-1)+2sinhcoshcos2x)/h

I'm stuck here... can't remember how to simplify this. Thanks. I also left out some steps, I don't know how to use the latex graphics yet and didn't want it to get to garbled.

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# Use definition of derivative

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