Tính các tổng sau (x^2 - 2) / (x(x - 1)^2) + (2 - x) / (x(x - 1)^2
Giải thích
\(\frac{{{x^2} - 2}}{{x{{\left( {x - 1} \right)}^2}}} + \frac{{2 - x}}{{x{{\left( {x - 1} \right)}^2}}}\)
\( = \frac{{{x^2} - 2 + 2 - x}}{{x{{\left( {x - 1} \right)}^2}}}\)\( = \frac{{{x^2} - x}}{{x{{\left( {x - 1} \right)}^2}}}\)
\( = \frac{{x\left( {x - 1} \right)}}{{x{{\left( {x - 1} \right)}^2}}} = \frac{1}{{x - 1}}\).