The quadratic equation 2x^2 + bx + 2 = 0 has a double root. Find all possible values of b.
If we have a double root , the disctiminant = 0 ....so......
b^2 - 4 * 2 * 2 = 0
b^2 - 16 = 0
b^2 = 16 take both roots
b = -4 and b = 4
