通分:(1)x分之3与1-x分之6与x的平方-x分之x+5 (2)(x-y)(x-2)分之3y的平方和(x-y)(2-x)分之3xy
问题描述:
通分:(1)x分之3与1-x分之6与x的平方-x分之x+5 (2)(x-y)(x-2)分之3y的平方和(x-y)(2-x)分之3xy
答
3与1-x分之6与x的平方-x分之x+5
3/x,6/(1-x),(x+5)/(x^2-x)
3/x=3(x-1)/x(x-1)
6/(1-x)=-6/(x-1)=-6x/x(x-1)
(x+5)/(x^2-x)=(x+5)/x(x-1)
(x-y)(x-2)分之3y的平方和(x-y)(2-x)分之3xy
3y^2/(x-y)(x-2)
3xy/(x-y)(2-x)=-3xy/(x-y)(x-2)
答
解(1):最简公分母是x(x-1)x分之3=3/x=3(x-1)/[x(x-1)]1-x分之6=6/(1-x)=-6/(x-1)=-6x/[x(x-1)]x的平方-x分之x+5=(x+5)/(x²-x)=(x+5)/[x(x-1)](2):最简公分母是(x-y)(x-2)(x-y)(x-2)分之3y的平方=3y²/[(x...