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cos^(2)5^(@)+cos^(2)10^(@)+cos^(2)15^(@)...

`cos^(2)5^(@)+cos^(2)10^(@)+cos^(2)15^(@)+.....+cos^(2) 90^(@)=`

A

7

B

`17/2`

C

`19/2`

D

`15/2`

Text Solution

Verified by Experts

The correct Answer is:
B
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Knowledge Check

  • cos^(2)1^(@)+ cos^(2)2^(@)+cos^(2)3^(@)+....+cos^(2)90^(@)=

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