Number of real solns

[Shreya Nair]

[Shirsendu Roy]

sin^5x+cos^3x  \leq |sin^5x+cos^3x|

\leq |sin^5x|+|cos^3x|

\leq |sin^2x|+|cos^2x|

=sin^2x+cos^2x

=1

or, sinx and cosx must be both 0 or 1. Putting that in given equation gives sinx=1 or cosx=1.

So, x=\pi/2+2n\pi or, x=2m\pi.

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