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The length of the longest interval in wh...

The length of the longest interval in which the function `3sinx-4sin^3x` is increasing is `pi/3` (b) `pi/2` (c) `(3pi)/2` (d) `pi`

A

`(pi)/(3)`

B

`(pi)/(2)`

C

`(pi)/(2)`

D

`(pi)`

Text Solution

Verified by Experts

The correct Answer is:
1
3 `sin x -4 sin^(3)x` = sin 3x which increases for
`3x in -(pi)/(2),(pi)/(2) or x in -(pi)/(6),(pi)/(6)` whose length is `(pi)/(3)`
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