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If x= cos 10^(@)cos 20^(@) cos 40^(@), t...

If `x= cos 10^(@)cos 20^(@) cos 40^(@),` then the value of x is

A

`1/4 tan 10^(@)`

B

` 1/8 cos 10^(@)`

C

`1/8 cosec 10^(@)`

D

`1/8 sec 10^(@)`

Text Solution

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The correct Answer is:
B
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