a*b= a-2b/2b,则3*4*1/2=几?

问题描述:

a*b= a-2b/2b,则3*4*1/2=几?

3*4*1/2 =[(3-2×4)/(2×4)]*1/2 =-5/8*1/2 =(-5/8-2×1/2)/(2×1/2) =-13/8