|x^2+x-28|=28

解

x^{2} + x - 28 = 28

x = - 8 or x = - 1 or x = 0 or x = 7

解答ステップ

x^{2} + x - 28 = 28

絶対規則を適用する:

∣ u ∣ = a, a > 0

の場合は

u = a

u = - a

x^{2} + x - 28 = - 28 or x^{2} + x - 28 = 28

x^{2} + x - 28 = - 28 or x^{2} + x - 28 = 28

(x = - 1 or x = 0) or (x = - 8 or x = 7)

x = - 8 or x = - 1 or x = 0 or x = 7