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Question
The roots of the quadratic equation `2x^2-x-6=0`
(a)`-2, 3/2` (b) `2, -3/2`
(c)` -2, 3/2` (d) `2, 3/2`
Solution
(b) `2, 3/2`
The given quadratic equation is `2x^2-x-6=0`
`2x^2-x-6=0`
⇒`2x^2-4x+3x-6=0`
⇒`2x(x-2)+3(x-2)=0`
⇒`(x-2) (2x+3)=0`
⇒`x-2=0 or 2x+3=0`
⇒ `x=2 or x=(-3)/2`
Thus, the roots of the given equation are `2 and (-3)/2`
Hence, the correct answer is option B.
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