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Question
If one of the equation x2 + ax + 3 = 0 is 1, then its other root is
Options
3
-3
2
1
Solution
Let `alpha and beta`be the roots of quadratic equation`x^2 + ax + 3 =0`in such a way that `alpha = 1`
Here, a = 1, b = a and ,c = 3
Then , according to question sum of the roots
`alpha + beta = (-b)/ a`
`1 + beta = (-a)/1`
`beta = -a -1`
And the product of the roots
`alpha . beta = 3/1`
`1 xx beta = 3`
`beta = 3`
Therefore, value of other root be `beta = 3`.
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