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प्रश्न
If the roots of the equation` ax^2+bx+c=0` are equal then c=?
(a)`b/(2a)` (b) `b/(2a)` (c) `-b^2/(4a)` (d) `B^2/(4a)`
उत्तर
(d) `b^2/(4a)`
It is given that the roots of the equation `(ax^2+bx+c=0)`are equal.
∴`(b^2-4ac)=0`
⇒`b^2=4ac`
⇒ `c=b^2/(4a)`
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