Question

If both the distinct roots of the equation `|sinx|^2+|sinx|+b=0in[0,pi]` are real, then the values of `b` are `[-2,0]` (b) `(-2,0)` `[-2,0]` (d) `non eoft h e s e`
A. `[-2, 0]`
B. `(-2, 0)`
C. `[-2, 0)`
D. none of these

Answer 1

Correct Answer - B
Given that `|sin x|^(2)+|sin x|+b=0`
`rArr |sin x|=(-1 pm sqrt(1-4b))/2`
`rArr 0 le (-1 pm sqrt(1-4b))/2 lt 1" "rArr -2 lt b lt 0`