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Let fk(x) = 1/k(sin^k x + cos^k x) where...

Let `f_k(x) = 1/k(sin^k x + cos^k x)` where `x in RR` and `k gt= 1.` Then `f_4(x) - f_6(x)` equals

A

`(1)/(3)`

B

`(1)/(4)`

C

`(1)/(12)`

D

`(1)/(6)`

Text Solution

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The correct Answer is:
C
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