a) x ² + x – 6/x ² + 4x + 3 . x ² – 4x – 5/x ² – 10x + 25 b) x(y ² – z) + y(x – xy)/(x – y) ² + (y – z) ² + (z – x) ² : xy ² – xz . (2y – z)/2(x ³+ y

Đáp án: a) $4\,{x}^{2}-11\,{x}^{-2}-10\,x+25$

b) $x \left( {y}^{2}-z \right) +{\frac {yx}{ \left( x-y \right) ^{2}}}-{
\frac {y{\it xy}}{ \left( x-y \right) ^{2}}}+{\frac {{x}^{2}}{{{\it xy
}}^{2}}}-2\,{\frac {zx}{{{\it xy}}^{2}}}+{\frac {{z}^{2}}{{{\it xy}}^{
2}}}-{\it xz} \left( 2\,y-{\frac {z}{2\,{x}^{3}+2\,{y}^{3}+2\,{z}^{3}-
6\,{\it xyz}}} \right) ^{-1}$

c) $1/6\,{\frac {12\,{x}^{5}+6\,{y}^{2}{x}^{2}+18\,{{\it yx}}^{2}{x}^{2}-4
\,{y}^{3}x+24\,{\it xy}\,{x}^{2}+3\,{y}^{2}}{{x}^{2}}}$

d) $1/5\,{\frac {5\,{x}^{5}y+25\,{y}^{2}{x}^{4}+5\,{{\it xy}}^{2}{x}^{2}-{
{\it xy}}^{3}+5\,y}{{x}^{2}}}$

e) ${\frac {2\,{x}^{4}+6\,{x}^{3}+9\,{x}^{2}+8\,x-50}{{x}^{2}}}$

g) $1/2\,{\frac {-4\,{y}^{3}{x}^{3}+2\,{x}^{5}+4\,{\it xy}\,{x}^{3}-4\,{{
\it xy}}^{2}x+{\it xy}\,x+{y}^{2}}{{x}^{3}}}$

Giải thích các bước giải: CHo nguyên cái đề luôn lười làm giải thích lắm