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Evaluate: (i) "sin""(3pi)/(8) (ii) "s...

Evaluate:
(i) `"sin""(3pi)/(8)` (ii) `"sin""(5pi)/(24)` (iii) `"tan""(pi)/(8)`.

Text Solution

Verified by Experts

The correct Answer is:
(i) `(sqrt(2+sqrt2))/(2)`
(ii) `(sqrt(6+3sqrt2)-sqrt(2-sqrt2))/(4)`
(iii) `sqrt2-1`
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MODERN PUBLICATION-TRIGONOMETRY-Exercise 3(g)Long Answer type Question-I
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  11. Prove that: s in^4pi/8+s in^4(3pi)/8+s in^4(5pi)/8+s in^4(7pi)/8=3/2

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  17. Prove that cos^2x+cos^2(x+pi/3)+cos^2(x-pi/3)=3/2

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