若a+b=3ab,则(2a+2b-ab)/(a+b+2ab)的值是多少?
问题描述:
若a+b=3ab,则(2a+2b-ab)/(a+b+2ab)的值是多少?
答
2a+2b-ab=2(a+b)-ab=6ab-ab=5ab a+b+2ab=3ab+2ab=5ab故原式=5ab/5ab=1
若a+b=3ab,则(2a+2b-ab)/(a+b+2ab)的值是多少?
2a+2b-ab=2(a+b)-ab=6ab-ab=5ab a+b+2ab=3ab+2ab=5ab故原式=5ab/5ab=1