Differentiation formula for Cos 2x=?

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Answer 1 · 2018-03-09T17:29:40

#=>d/dx(Cos2x)=-2sin2x#

We have:

#d/dx(Cos2x)#

Two rules to remember here:

#d/dx(cosx)=-sinx#

#d/dx(g(h(x)))=g'(h(x))*h'(x)#

#d/dx(x^n)=nx^(n-1)# where #n# is a constant.

Therefore:

#d/dx(Cos2x)=-sin2x*d/dx(2x)#

#=>d/dx(Cos2x)=-sin2x*2#

#=>d/dx(Cos2x)=-2sin2x#