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

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Question

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

Sum
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Solution

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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Chapter 3: Trigonometric Functions - Exercise 3.3 [Page 73]

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NCERT Mathematics [English] Class 11
Chapter 3 Trigonometric Functions
Exercise 3.3 | Q 2 | Page 73

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