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If (1 + tan alpha) (1 + tan 4 alpha) = 2...

If `(1 + tan alpha) (1 + tan 4 alpha) = 2, alpha in (0, (pi)/(16))`, then `alpha =`

A

`(pi)/(20)`

B

`(pi)/(30)`

C

`(pi)/(40)`

D

`(pi)/(60)`

Text Solution

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The correct Answer is:
A
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