How to find result ?

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1 Answer
Mar 29, 2018

The solution set is the singleton set {0}

Explanation:

Since sin2x+cos2x=1 , sin6xsin2x and cos10xcos2x (the last two following from the fact that both sin2x and cos2x are bounded above by 1, we have

sin6x+cos10x1

and thus

2x2sin6x+cos10x10 is only possible if

x=0