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प्रश्न
Prove that `2 sin^2 pi/6 + cosec^2 (7pi)/6 cos^2 pi/3 = 3/2`
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उत्तर
Left side = `2 sin^2 pi/6 + cosec^2 (7pi)/6 cos^2 pi/3 = 3/2`
= 2 `(1/2)^2 + cosec^2 (π+π/6) x (1/2)^2`
= `2xx 1/4+ (-cosec pi /6)^2 (1/4)`
`1/2+(- 2) ^2 (1/4)`
= `1/2+ 4/4 = 1/2 + 1 = 3/2` = Right Side.
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