(1)-9+12-3+8;
(2)-20+(-14)-(-18)-13;
(3)48×(-+-);
(4);
(5)(-48)÷÷(-12)×;
(6);
(7)-12+3×(-2)2+(-6)÷(-)2;
(8)(-2)3-2×(-3)+|2-5|-(-1)2010.
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解:(1)-9+12-3+8
=3-3+8,
=0+8
=8;
(2)-20+(-14)-(-18)-13
=-20-14+18-13
=-29;
(3)48×(-+-)
=48×(-)+48×-48×
=-8+36-4
=24;
(4)
=81×××
=1;
(5)(-48)÷÷(-12)×
=48×××
=4;
(6)
=5÷[+]×4
=5÷×4
=24;
(7)-12+3×(-2)2+(-6)÷(-)2
=-1+3×4-6÷
=-1+12-54
=-43;
(8)(-2)3-2×(-3)+|2-5|-(-1)2010
=-8+6+3-1
=-2+3-1
=0.
解析分析:(1)(2)(4)从左往右依次计算即可;
(3)(5)根据乘法分配律计算即可;
(6)先算括号里面的,再算括号外面的;
(7)先乘方后乘除最后算加减;
(8)先乘方和绝对值后,再算乘除最后算加减.
点评:本题考查的是有理数的运算能力.注意:要正确掌握运算顺序,即乘方运算(和以后学习的开方运算)叫做三级运算;乘法和除法叫做二级运算;加法和减法叫做一级运算.在混合运算中要特别注意运算顺序:先三级,后二级,再一级;有括号的先算括号里面的;同级运算按从左到右的顺序.