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cos20^(@).cos40^(@).cos60^(@).cos80^(@) ...

`cos20^(@).cos40^(@).cos60^(@).cos80^(@)` is :

A

1/16

B

1/50

C

1/24

D

1/25

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The correct Answer is:
A
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QUANTUM CAT-TRIGONOMETRY-QUESTION BANK
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  12. Find the value of cot3theta:

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  15. Find the value of tanA+tanB+tanC, if A+B+C=pi:

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  16. If cos B=(sinA)/(2sinC), find the nature of triangle :

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  17. If the angles of a triangle are in the ratio 1:2:3 and its circumradiu...

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  18. If a=1, b=sqrt3 and angleA=30^(@), find the value of the angle B:

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  19. Find B and C of a triangle ABC, if b = 2 cm, c = 1 cm and A=60^(@).

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  20. In a triangle ABC, a=1cm, b=sqrt3 and C=(pi)/(6), find the third side ...

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