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DEMO: Sum and product of roots

Worked examples

• $x^2 - 4x + 1$: sum $= -\frac{-4}{1} = 4$.
• $2x^2 + x - 6$: product $= \frac{-6}{2} = -3$.
• $2x^2 + 8x + 3$: sum $= -\frac{8}{2} = -4$.

Key points

• For $ax^2 + bx + c = 0$, the sum of roots is $-\frac{b}{a}$.
• $a = 2$, $b = -6$.
• For $ax^2 + bx + c = 0$, the product of roots is $\frac{c}{a}$.
• $a = 1$, $c = 10$.
• Sum of roots $= -\frac{b}{a}$.
• $a = 3$, $b = 12$.

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