If cos(A-B)=3/5 and tan A tan B=2, then ...

If `cos(A-B)=3/5 and tan A tan B=2,` then (a) `cos Acos B=1/5` (b) `sin A sin B=-2/5` (c) `cos AcosB=-1/5` (d) `sin A sinB=-1/5`

A

`cosAcosB=1/5`

B

`sinAsinB=-2/5`

C

`cos(A+B)=-1/5`

D

none of these

Verified by Experts

The correct Answer is:

A

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