2分之1+2×3分之2+2×3×4分之3

问题描述:

2分之1+2×3分之2+2×3×4分之3
急需简便方法,要简便的

答:
1/2+2/(2×3)+3/(2×3×4)
=1/2+2×(1/2-1/3)+1/(2×4)
=1/2+1-2/3+(1/2)×(1/2-1/4)
=3/2-2/3+1/4-1/8
=18/12-8/12+1/8
=10/12+1/8
=20/24+3/24
=23/24