1.

If `a in (-1,1),`then roots of the quadratic equation `(a-1)x^2+a x+sqrt(1-a^2)=0`area. realb. imaginaryc. both equald. none of theseA. realB. imaginaryC. both equalD. none of these

Answer» Correct Answer - 1
`(a - 1) x^(2) + ax + sqrt(1 - a^(2)) = 0`
`therefore D = a^(2) - 4(a - 1) sqrt(1 - a^(2))`
`= a^(2) - 4a sqrt(1 - a^(2)) + 4 sqrt(1 - a^(2))`
`= (a - 2 sqrt(1 - a^(2)))^(2) + 4sqrt(1 - a^(2))(1 - sqrt(1 - a^(2)))`
`ge 0` for `a in (-1, 1)`
Hence roots are real but not equal.


Discussion

No Comment Found

Related InterviewSolutions