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If the sum of the roots of the equation ...

If the sum of the roots of the equation `ax^(2) + bx+ c = 0` is equal to the sum of their squares then

A

`a^(2) + b^(2) = c^(2)`

B

`a^(2) + b^(2) = a + b`

C

`ab+ b^(2) = 2ac`

D

`ab-b^(2) = 2ac`

Text Solution

Verified by Experts

The correct Answer is:
C

`ax^(2) + bx + c = 0 `
Let the root be `alpha and beta`
` alpha + beta = -b/a, alpha.beta = c/a`
` rArr alpha + beta = alpha^(2) + beta^(2) " "`…(given)
` rArr alpha+beta = (alpha + beta)^(2) - 2 alpha beta `
` rArr -b/a = (-b/a)^(2) - (2c)/a`
` rArr b^(2) + ab = 2ac`
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