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If cos(x-y), cosx and cos(x+y) are in H....

If `cos(x-y), cosx and cos(x+y)` are in H.P., then `|cos x sec (y)/(2)|` equals

A

1

B

2

C

`sqrt(2)`

D

None of these.

Text Solution

Verified by Experts

The correct Answer is:
C
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