Prove that `f(x)=sinx+sqrt(3)cosx` has maximum value at `x=pi/6` .

Explanation

`f(x)=sinx+ sqrtx cosx`


`f ′ (x)=cosx− sqrt3 sinx`


f ′ (x)=0 for critical points


`⇒cosx−sqrt 3 sinx=0`


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