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If sin(theta+18^(@))=cos60^(@)(0lttheta...

If `sin(theta+18^(@))=cos60^(@)(0ltthetalt90^(@))` , then the value of `cos5theta` is

A

`(1)/(2)`

B

0

C

`(1)/(sqrt(2))`

D

1

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The correct Answer is:
A
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KIRAN PUBLICATION-TRIGONOMETRY -TYPE - II
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