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Find the value of cos^(4)""(pi)/(8)+cos^...

Find the value of `cos^(4)""(pi)/(8)+cos^(4)""(3pi)/(8)+cos^(4)""(5pi)/(8)+cos^(4)""(7pi)/(8)`.

A

0

B

`1//2`

C

`3//2`

D

1

Text Solution

Verified by Experts

The correct Answer is:
C
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OBJECTIVE RD SHARMA ENGLISH-TRIGONOMETRIC RATIOS AND IDENTITIES-Exercise
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  2. If theta lies in the first quardrant and costheta=(8)/( 17 ), then fi...

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  3. Find the value of cos^(4)""(pi)/(8)+cos^(4)""(3pi)/(8)+cos^(4)""(5pi)/...

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  6. If theta lies in the first quadrant which of the following in not true

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  8. The interior angles of a polygon are in A.P. the smallest angle is 120...

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  13. If (x)/(a) cos alpha+ (y)/(b) sin alpha = 1, (x)/(a) cos beta + (y)/(b...

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  14. The value of theta lying between 0 and pi/2 and satisfying |[1+sin^2th...

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  18. The value of sin(pi+theta)sin(pi-theta)cosec^(2)theta is equal to

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  19. If (sin(x+y))/(sin(x-y))=(a+b)/(a-b) , show that (tanx)/(tany)=a/b .

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