Question

If the roots of the equation x² - bx + c = 0 be two consecutive integers, then b² - 4c equals
(a) -2
(b) 3
(c) 2
(d) 1

Answer 1

Answer:

Answer is 1. Option d

Step-by-step explanation:

Let one root is a

∴ Other root will be a+1

(x-a)(x-(a+1))=x²-(2a+1)x+a(a+1)

Compare this with x²-bx+c

∴b=(2a+1) and c=a(a+1)

∴b²-4c=(2a+1)²-4a(a+1)

          =4a²+4a+1-4a²-4a

          =1