Question

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)`

Answer 1

(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)`