x^2 -2x - 13 = 0
This is of the form ax^2 + bx + c = 0 where a = 1, b = -2, c = -13
We use the quadratic formula: x = [-b ± sqrt(b^2 - 4ac)] / 2a
x = [-(-2) ± sqrt {(-2)^2 - 4 * 1 * -13}] / 2(1)
x = [2 ± sqrt {4 + 52}] / 2
x = (2 ± sqrt 56) / 2
x = [2 ± 2 sqrt 14] / 2
x = 1± sqrt 14
Solution: x = {(1 - sqrt 14), (1 + sqrt 14)}.
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Masters Degree