The roots of a quadratic equation are -3 and 1. Find its equation.
-
A.
(x^{2} – 3x + 1 = 0) -
B.
(x^{2} – 2x + 1 = 0) -
C.
(x^{2} + 2x – 3 = 0) -
D.
(x^{2} + x – 3 = 0)
Correct Answer: Option C
Explanation
Given the roots of an equation such that you can find the sum and product of the roots, the equation can be given as:
(x^{2} – (alpha + beta)x + (alpha beta) = 0 )
(alpha + beta = -3 + 1 = -2)
(alpha beta = -3 times 1 = -3)
Equation: (x^{2} – (-2)x + (-3) = 0 implies x^{2} + 2x – 3 = 0)