Given a + B = 3, ab = 2, find the value of a-b

Given a + B = 3, ab = 2, find the value of a-b

(a-b) = a ^ 2-2ab + B ^ 2 = a ^ 2 + B ^ 2-2ab = - (a ^ 2-B ^ 2) - 2Ab = - (a + b) (a-b) - 2Ab so (a-b) = - (a + b) (a-b) - 2Ab, that is, (a-b) = - 3 (a-b) - 4 = - 4 (a-b) so (a-b) = - 1