已知a≠b,a≠0,b≠0,a+b≠0,x=4ab/(a+b),求：(2+2a)/(x-2a)+(x+2b)/(x-2b)的值。

熱心網(wǎng)友

(x+2a)/(x-2a)+(x+2b)/(x-2b) (2+2a???)=[4ab/(a+b)+2a]/[4ab/(a+b)-2a]/[4ab/(a+b)+2b]/[4ab/(a+b)-2b]=2a[2b+(a+b)]/{2a[2b-(a+b]}+2b[2a+(a+b)]/{2a[-(a+b)]}=(a+3b)/(b-a)+(3a+b)/(a-b)=[-(a+3b)+(3a+b)]/(a-b)=2(a-b)/(a-b)=2