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Prove that 2sin2 π6+cosec2 7π6cos2 π3=32

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प्रश्न

Prove that  `2 sin^2  pi/6 + cosec^2  (7pi)/6 cos^2  pi/3 = 3/2`

योग
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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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अध्याय 3: Trigonometric Functions - EXERCISE 3.3 [पृष्ठ ६७]

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एनसीईआरटी Mathematics [English] Class 11
अध्याय 3 Trigonometric Functions
EXERCISE 3.3 | Q 2. | पृष्ठ ६७

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