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问题: 数学高手,快快来。急啊……

简算。全部要过程

33333*66666
1997*19981998-1998*19971997
1/1*2 + 1/2*3 + 1/3*4 +……+ 1/99*100
(1又3/4 - 7/8 - 7/12)*(-1又1/7)
(-3)的平方*[(-2/3)+(-5/9)]
(5/9 - 5/6 +1/4)除以(-1/36)
(-19又18/19)*38

解答:

33333*66666=3*6*11111^2=18*123454321=2222177778
1997*19981998-1998*19971997
=1997*1998*10001-1998*1997*10001=0
1/1*2 + 1/2*3 + 1/3*4 +……+ 1/99*100
=(2-1)/1*2+(3-2)/2*3+(4-3)/3*4 +……+(100-99)/99*100
=1-1/100=99/100
(1又3/4 - 7/8 - 7/12)*(-1又1/7)
=(7/4-7/8-7/12)*(-8/7)
=-2+1+2/3=-1/3
(-3)^2*[(-2/3)+(-5/9)]
=9*[(-2/3)+(-5/9)]
=-6--5=-11
(5/9 - 5/6 +1/4)除以(-1/36)
=(5/9 - 5/6 +1/4)*(-36)
=-20+30-9=1
(-19又18/19)*38
=-(19+18/19)*38
=-(722+36)
=-758