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.计算:(每题4分共24分)
(1)   
(2) 
(3)   
(4)
(5)       
(6)
答案:(1)20 (2)-148 (3)-3a-11 (4)-13m+22n (5) 81 (6)
试题分析(1)有理数的加减,注意算式中的相反数之和为0;(2)运算中注意运算顺序;
(3)(4)先去括号再合并同类型进行化简;
(5)把除法转化为乘法后,运用分配律进行简便计算;
(6)先算乘方再进行有理数运算.
试题解析:
(1)    
=22+(-2)+(-2014)+2014                           
=20 
(2)     
=21-169                                    
=-148
(3)   
="a" 2—6a-7-a2+3a-4                         
=" a" 2-a2-6a+3a-7-4                           
=-3a-11   
(4)
=5m+5n-12m+8n-6m+9n
=5m-12m-6m+5n+8n+9n
=-13m+22n
(5)       
=×(-36)-3×(-36)+×(-36)-×(-36)        
=-18+108-30+21                                                                
="81"
(6)   
=4×[(-9)×-0.8]×(-)  
= 4×[-1-0.8]×(-)                                     
=
考点:整式的加减,有理数运算.