|x^2-7|=2

解

x^{2} - 7 = 2

x = - 3 or x = - 5 or x = 5 or x = 3

十進法表記

x = - 3, x = - 2.23606 \dots, x = 2.23606 \dots, x = 3

解答ステップ

x^{2} - 7 = 2

絶対規則を適用する:

∣ u ∣ = a, a > 0

の場合は

u = a

u = - a

x^{2} - 7 = - 2 or x^{2} - 7 = 2

x^{2} - 7 = - 2 or x^{2} - 7 = 2

(x = - 5 or x = 5) or (x = - 3 or x = 3)

x = - 3 or x = - 5 or x = 5 or x = 3