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cos 9^(@) - sin 9^(@)=...

`cos 9^(@) - sin 9^(@)=`

A

`-(sqrt(5-sqrt5))/(2)`

B

`(5 + sqrt(5))/(4)`

C

`(1)/(2) sqrt(5-sqrt(5))`

D

`sqrt(5-sqrt(5))`

Text Solution

Verified by Experts

The correct Answer is:
C
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