Question

x³ -11x² + 30x = 0. Tìm x

Answer 1

\(=x^3-5x^2-6x^2+30x\)

\(=x^2\left(x-5\right)-6x\left(x-5\right)\)

\(=\left(x^2-6x\right)\left(x-5\right)\)

\(=x\left(x-5\right)\left(x-6\right)=0\)

\(\Rightarrow\left[\begin{array}{nghiempt}x=0\\x=5\\x=6\end{array}\right.\)

Answer 2

x³ - 11x² + 30x = 0

x(x² - 11x + 30) = 0

x(x² - 5x - 6x + 30) = 0

x[x(x - 5) - 6(x - 5)] = 0

x(x - 5)(x - 6) = 0

\(\left[\begin{array}{nghiempt}x=0\\x-5=0\\x-6=0\end{array}\right.\)

\(\left[\begin{array}{nghiempt}x=0\\x=5\\x=6\end{array}\right.\)