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cos20^(@)cos40^(@)-sin5^(@)sin25^(@)=...

`cos20^(@)cos40^(@)-sin5^(@)sin25^(@)=`

A

0

B

`(sqrt(3)+1)/4`

C

`(sqrt(3)-1)/2`

D

`(sqrt(3)-1)/4`

Text Solution

Verified by Experts

The correct Answer is:
B
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