Question

tìm x, biết:

(x²+1)(x-2)+2x=4

Answer 1

\(\left(x^2+1\right)\left(x-2\right)+2x=4\)

\(\Rightarrow\left(x^2+1\right)\left(x-2\right)+2\left(x-2\right)=0\)

\(\Rightarrow\left(x-2\right)\left(x^2+3\right)=0\)

=> x = 2 (vì x^2 + 3 > 0)

Answer 2

Ta có: \(\left(x^2+1\right)\left(x-2\right)+2x=4\)

\(\Leftrightarrow\left(x^2+1\right)\left(x-2\right)+2x-4=0\)

\(\Leftrightarrow\left(x-2\right)\left(x^2+1+2\right)=0\)

\(\Leftrightarrow x-2=0\)

hay x=2