If-cos-2-x-1-cos-2-x-2-cos-2-x-3-cos-2-x-4-cos-2-x-5-5-then-sin-x-1-2sin-x-2-3sin-x-3-4sin-x-4-5sin-x-5-is-less-than-or-equal-to-

Question Number 18719 by Tinkutara last updated on 28/Jul/17

If \cos^{2} x_{1} + \cos^{2} x_{2} + \cos^{2} x_{3} + \cos^{2} x_{4}

+ \cos^{2} x_{5} = 5, then \sin x_{1} + 2 \sin x_{2} +

3 \sin x_{3} + 4 \sin x_{4} + 5 \sin x_{5} is less than

or equal to

Commented by mrW1 last updated on 28/Jul/17

0

\cos x_{i} = \pm 1 \Rightarrow \sin x_{i} = 0

\Rightarrow Σ (i \sin x_{i}) = 0

Commented by Tinkutara last updated on 29/Jul/17

Thanks Sir!