JAMB - Mathematics (1982 - No. 30)
The solution to the quadratic equation 5 + 3x - 2x2 = 0 is
(\(\frac{5}{2}\), 1)
(5, 3)
-(\(\frac{5}{2}\), -1)
(\(\frac{5}{2}\), -1)
설명
5 + 3x - 2x2 = 0, (x + 1)(5 - 2x) (expand to check)
(x + 1)(5 - 2x) = 0
when x = 1 = 0, x = -1
when 5 - 2x = 0, x = \(\frac{5}{2}\) - 1
(x + 1)(5 - 2x) = 0
when x = 1 = 0, x = -1
when 5 - 2x = 0, x = \(\frac{5}{2}\) - 1