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The number of values of yin[-2pi,2pi] sa...

The number of values of `yin[-2pi,2pi]` satisfying the equation `|sin2x|+|cos2x|=|siny|` is 3 (b) 4 (c) 5 (d) 6

A

3

B

4

C

5

D

6

Text Solution

Verified by Experts

The correct Answer is:
B

We have `|sin 2x|+|cos 2 x|=|sin y|`
on squaring, we get `1 +|sin 4x|= sin^(2) y`
`L.H.S. ge 1`, but `R.H.S. le 1`
So solution is possible only when `|sin y|=1`, Thus,
`sin y= pm 1" "rArr y= pm pi/2, pm (3pi)/2`
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