How do you differentiate $2cos^2(x)$ ?

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Answer 1 · 2017-01-19T08:10:51

$(dy)/(dx) =-4cosxsinx$

To differentiate $y=2cos^2x$ we need the chain rule

$(dy)/(dx)=(dy)/(du)xx(du)/(dx)$

let $u=cosx=>y=2u^2$

$(du)/(dx)=-sinx$

$(dy)/(du)=4u$

$:.(dy)/(dx)=4uxx(-sinx)$

substitute back for $u$

$(dy)/(dx) =-4cosxsinx$

How do you differentiate 2cos^2(x)2cos^2(x)?