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If the roots of 3x^(2)- 12x +k = 0 are c...

If the roots of `3x^(2)- 12x +k = 0` are complex, then find the range of k.

A

`k lt 22`

B

`a lt - 10`

C

`k gt 11`

D

`k gt 12`

Text Solution

Verified by Experts

The correct Answer is:
D
Given the roots of the given equation are complex
`rArr b^(2) - 4 ac lt 0`
`rArr (-12)^(2) - 4(3) k lt 0`
`144 - 12 k lt 0`
`- 12 k lt - 144`
`12 k gt 144`
`k lt 12`.
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