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Suppose A and B are two angles such that...

Suppose A and B are two angles such that A,B `in(0,pi)` and satisfy sinA + sinB = 1 and cosA + cosB = 0. Then the value of 12cos2A + 4cos2B is _______

A

6

B

7

C

8

D

9

Text Solution

Verified by Experts

The correct Answer is:
C
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Knowledge Check

  • If sinA+sinB=l and cosA-cosA-cosB=m , then cos(A-B)=

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