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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

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`|sin2x| +|cos2x| = |siny|`
`=>(|sin2x| +|cos2x|)^2 = (|siny|)^2`
`=>sin^2 2x+cos^2 2x +2|sin2xcos2x| = sin^2y`
`=>1+|sin4x| = sin^2y`
`=>1-sin^2y = -|sin4x|`
`=>cos^2y = -|sin4x|`
Now, `cos^2y` will always be positive and `-|sin4x|` will always be negative.
So, only possible value that will satisfy the equation will be when both sides are `0`.
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