Đáp án:
$=\dfrac{7}{4}$
Giải thích các bước giải:
$(3x^{2}-x+1)(x-1)+$ $x^{2}(4-3x)=$ $\dfrac{5}{2}$
$3x^{3}-$ $4x^{2}+2x-1-$ $3x^{3}+$ $4x^{2}=$ $\dfrac{5}{2}$
$2x-1=\dfrac{5}{2}$
$2x=\dfrac{5}{2}+1$
$2x=\dfrac{7}{2}$
$x=\dfrac{7}{2}:2$
$x=\dfrac{7}{2}.$ $\dfrac{1}{2}$
$x=\dfrac{7}{4}$