Question

If α and β are the roots of x2+ 5x + a = 0 and α + 5β = (–1), then find ‘a’

Answer 1

x² + 5x + a = 0

If A & B are two roots then :

A + B = -5 and AB = a

2A + 5B = 2(A + B) + 3B = -1

=> 2 x -5 + 3B = -1

=> B = 3

=> A = -5 - 3 = -8

=> AB = a = -8 x 3 = -24

:-)