Tìm x biết: x^3 - 3x^2 + 3x - 1 = 0
Giải thích
Ta có: x3−3x2+3x−1=0
⇔x3−1−3xx−1=0
⇔x−1x2+x+1−3xx−1=0
⇔x−1x2+x+1−3x=0
⇔x−1x2+x+1−3x=0
⇔x−1x2−2x+1=0
⇔x−1x−12=0
⇔x−13=0⇔x=1
Vậy x=1.
Ta có: x3−3x2+3x−1=0
⇔x3−1−3xx−1=0
⇔x−1x2+x+1−3xx−1=0
⇔x−1x2+x+1−3x=0
⇔x−1x2+x+1−3x=0
⇔x−1x2−2x+1=0
⇔x−1x−12=0
⇔x−13=0⇔x=1
Vậy x=1.