1)8/3+(-5/2)+(+16/3)+(-11/2)+(3/4-2/3-1/6)X12=?
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1)8/3+(-5/2)+(+16/3)+(-11/2)+(3/4-2/3-1/6)X12=?
2)4/9X(-9/14)-(-5/9)X(-9/14)-9/14X(-11/9)=?
3)1/5X9+1/9X13+1/13X17+...1/101X105=?
4)[(-1/2)的平方+(-1/4)X16+4的平方]X[(-3/2)-3]+441/8+1399/14+1399/14X(-7)+1399/2
5)(-1)+(-1)的平方+(-1)的立方+...+(-1)的99次方+(-1)的100次方+1/4+1/28+1/70+...+1/9700
2)4/9X(-9/14)-(-5/9)X(-9/14)-9/14X(-11/9)=?
3)1/5X9+1/9X13+1/13X17+...1/101X105=?
4)[(-1/2)的平方+(-1/4)X16+4的平方]X[(-3/2)-3]+441/8+1399/14+1399/14X(-7)+1399/2
5)(-1)+(-1)的平方+(-1)的立方+...+(-1)的99次方+(-1)的100次方+1/4+1/28+1/70+...+1/9700
1)8/3+(-5/2)+(+16/3)+(-11/2)+(3/4-2/3-1/6)X12
=(8/3+16/3)-(5/2+11/2)+(3*3-2*4-2)
=8-8+9-8-2
=-1
2)4/9X(-9/14)-(-5/9)X(-9/14)-9/14X(-11/9)
=-4/14-5/14+11/14
=2/14
=1/7
3)1/5X9+1/9X13+1/13X17+...1/101X105
=1/4(1/5-1/9)+1/4(1/9-1/13)+1/4(1/13-1/17)+…1/4(1/101-1/105)
=1/4(1/5-1/9+1/9-1/13...+1/101-1/105)
=1/4(1/5-1/105)
=1/21
4)[(-1/2)的平方+(-1/4)X16+4的平方]X[(-3/2)-3]+441/8+1399/14+1399/14X(-7)+1399/2
=(1/4-4+16)(-9/2)+441/8+1399/14+1399/14X(-7)+1399/14*7
=49/4*(-9/2)+441/8+1399/14+0
=-441/8+441/8+1399/14
=1399/14
5)(-1)+(-1)的平方+(-1)的立方+...+(-1)的99次方+(-1)的100次方+1/4+1/28+1/70+...+1/9700
(因为(-1)+(-1)的平方+...+(-1)的99次方+(-1)的100次方=0 )
所以:
原式=1/4+1/28+...+1/9700
=1/1*4+1/4*7+……+1/97*100
=1/3(1-1/4+1/4-1/7+...+1/97-1/100)
=1/3(1-1/100)
=33/100=0.33
=(8/3+16/3)-(5/2+11/2)+(3*3-2*4-2)
=8-8+9-8-2
=-1
2)4/9X(-9/14)-(-5/9)X(-9/14)-9/14X(-11/9)
=-4/14-5/14+11/14
=2/14
=1/7
3)1/5X9+1/9X13+1/13X17+...1/101X105
=1/4(1/5-1/9)+1/4(1/9-1/13)+1/4(1/13-1/17)+…1/4(1/101-1/105)
=1/4(1/5-1/9+1/9-1/13...+1/101-1/105)
=1/4(1/5-1/105)
=1/21
4)[(-1/2)的平方+(-1/4)X16+4的平方]X[(-3/2)-3]+441/8+1399/14+1399/14X(-7)+1399/2
=(1/4-4+16)(-9/2)+441/8+1399/14+1399/14X(-7)+1399/14*7
=49/4*(-9/2)+441/8+1399/14+0
=-441/8+441/8+1399/14
=1399/14
5)(-1)+(-1)的平方+(-1)的立方+...+(-1)的99次方+(-1)的100次方+1/4+1/28+1/70+...+1/9700
(因为(-1)+(-1)的平方+...+(-1)的99次方+(-1)的100次方=0 )
所以:
原式=1/4+1/28+...+1/9700
=1/1*4+1/4*7+……+1/97*100
=1/3(1-1/4+1/4-1/7+...+1/97-1/100)
=1/3(1-1/100)
=33/100=0.33
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