Let e and d denote the solutions of 2x^2 + 3x - 5=0. What is the value of (d-1)(e-1)?
By the quadratic formula, the roots are x = -1 +/- sqrt(7/2)
Then (d - 1)(e - 1) = (-1 + sqrt(7/2) - 1)(-1 - sqrt(7/2) - 1) = 1/2.
Like so:
