Tìm x, biết: 5x(x – 1) = x – 1
Giải thích
5x(x – 1) = x – 1
⇔ 5x(x – 1) – (x – 1) = 0
⇔ (5x – 1)(x – 1) = 0
⇔ 5x – 1 = 0 hoặc x – 1 = 0
• x – 1 = 0 ⇔ x = 1
• 5x – 1 = 0 ⇔ x = 1/5
Vậy x = 1 hoặc x = 1/5.
5x(x – 1) = x – 1
⇔ 5x(x – 1) – (x – 1) = 0
⇔ (5x – 1)(x – 1) = 0
⇔ 5x – 1 = 0 hoặc x – 1 = 0
• x – 1 = 0 ⇔ x = 1
• 5x – 1 = 0 ⇔ x = 1/5
Vậy x = 1 hoặc x = 1/5.