计算题:(x^2-a^2)/(x^2-9a^2)+(x-2a)^2/(9a^2-x^2)+(5a^2-4ax)/(x^2-9a^2)

问题描述:

计算题:(x^2-a^2)/(x^2-9a^2)+(x-2a)^2/(9a^2-x^2)+(5a^2-4ax)/(x^2-9a^2)

  (x^2-a^2)/(x^2-9a^2)+(x-2a)^2/(9a^2-x^2)+(5a^2-4ax)/(x^2-9a^2)  =(x^2-a^2)/(x^2-9a^2)-(x-2a)^2/(x^2-9a^2)+(5a^2-4ax)/(x^2-9a^2)  =[(x^2-a^2)-(x^2-4ax+4a^2)+(5a^2-4ax)]/(x^2-9a^2)  =[x^2-a^2-...