已知abc=1求a/[abc+ab+a+1]+b/bcd+bc+b+1]+c/[cda+cd+c+1]+d/[dab+da+d+1]
问题描述：
已知abc=1求a/[abc+ab+a+1]+b/bcd+bc+b+1]+c/[cda+cd+c+1]+d/[dab+da+d+1]
快点谢谢
要详细过程
答
a/(abc+ab+a+1)+b/(bcd+bc+b+1)+c/(cda+cd+c+1)+d/(dab+da+d+1) =a/(1/d+ab+a+1)+b/(bcd+bc+b+1)+c/(1/b+cd+c+1)+d/(dab+da+d+1) =ad/(abd+ad+d+1)+b/(bcd+bc+b+1)+bc/(bcd+bc+b+1)+d/(dab+da+d+1) =(ad+d)/(abd+ad+...