What is the value of ax2 - bx - c at x - -ba-

The roots of a quadratic equation $a x^{2} + b x + c = 0$ are given by $\frac{- b \pm \sqrt{b^{2} - 4 a c}}{2 a}$ , provided $b^{2} - 4 a c \geq 0$ .

Q. Prove the root of equation

{a x}^{2} + b x + c = 0

\Rightarrow x = \frac{- b \pm \sqrt{b^{2} - 4 a c}}{2 a}

If b² – 4ac = 0 then The roots of the Quadratic equation ax² + bx + c = 0 are given by :

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What is the value of ax2+bx+c at x=−ba?

The correct option is B cGiven expression is f(x)=ax2+bx+cWe need to find value of f(x) at x=−baf(−ba)=a×(−ba)2+b×(−ba)+cf(−ba)=b2a−b2a+cf(−ba)=c

What is the value of $a x^{2} + b x + c$ at $x = \frac{- b}{a}$ ?

The correct option is B $c$
Given expression is $f (x) = a x^{2} + b x + c$
We need to find value of $f (x)$ at $x = \frac{- b}{a}$
$f (\frac{- b}{a}) = a \times {(\frac{- b}{a})}^{2} + b \times (\frac{- b}{a}) + c$
$f (\frac{- b}{a}) = \frac{b^{2}}{a} - \frac{b^{2}}{a} + c$
$f (\frac{- b}{a}) = c$