初一数学题.今晚就要答案,越早越好!有过程.如果规定符合“*”的意义是a*b=a+b/ab,试求2*(-3)*4的值

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初一数学题.今晚就要答案,越早越好!有过程.
如果规定符合“*”的意义是a*b=a+b/ab,试求2*(-3)*4的值

25/4

2*(-3)=2+(-3)/(2乘(-3))=5/2
(5/2)*4=(5/2)+4/((5/2)乘4)=2.9

2*(-3)*4
=[2*(-3)]*4
=[2+(-3)/(-6)]*4
=(2+1/2)*4
=5/2*4
=5/2+(5/2)/10
=5/2+5/20
=5/2+1/4
=10/4+1/4
=11/4

2*(-3)*4
=[2*(-3)]*4
=[2+(-3)/(-6)]*4
=(2+1/2)*4
=5/2*4
=5/2+(5/2)/10
=5/2+5/20
=5/2+1/4
=10/4+1/4
=11/4

6.125
2*(-3)=[2+(-3)]/(2×(-3))=1/6
(1/6)*4=6.125