Tìm x biết 8x^3 – 12x^2 + 6x – 1 = 0
Tìm x biết 8x3 – 12x2 + 6x – 1 = 0.
8x3 – 12x2 + 6x – 1 = 0
⇔ (2x)3 – 3. (2x)2. 1 + 3. 2x . 12 – 13 = 0
⇔ (2x – 1)3 = 0
⇔ 2x – 1 = 0
⇔\(x = \frac{1}{2}\).