(x-2 - 5/(x+2) ) / ((x-3)/(2x+4))分子分母同乘(x+2)�0�2((x-2)(x+2) - 5) / �0�2((x-3)/2)2(x^2 - 9) / (x-3)2(x-3)(x+3)/(x-3)2(x+3)2(√2 -3 + 3 )2√2
