题目内容
计算
(1)4-(-3)×(-1)-8×(-
)3×|-2-3|
(2)(-5)3×(-
)-32÷(-2)2×(+
)
(3)13+(+7)-(-20)-(-40)-(+6)
(4)(-7)-(+5)+(+3)-(-9)
(5)18-6÷(-2)×(-
)
(6)(-4)2×[-
+(-
)].
(1)4-(-3)×(-1)-8×(-
| 1 |
| 2 |
(2)(-5)3×(-
| 3 |
| 5 |
| 5 |
| 4 |
(3)13+(+7)-(-20)-(-40)-(+6)
(4)(-7)-(+5)+(+3)-(-9)
(5)18-6÷(-2)×(-
| 1 |
| 3 |
(6)(-4)2×[-
| 3 |
| 4 |
| 5 |
| 8 |
分析:(1)(2)(6)按照有理数混合运算的顺序,先乘方后乘除最后算加减,有括号的先算括号里面的;
(3)(4)先化简,再计算即可;
(5)按照有理数混合运算的顺序,先乘除后算加减,有括号的先算括号里面的.
(3)(4)先化简,再计算即可;
(5)按照有理数混合运算的顺序,先乘除后算加减,有括号的先算括号里面的.
解答:解:(1)4-(-3)×(-1)-8×(-
)3×|-2-3|
=4-3+8×
×5
=4-3+5
=6;
(2)(-5)3×(-
)-32÷(-2)2×(+
)
=-125×(-
)-32÷4×
=75-10
=65;
(3)13+(+7)-(-20)-(-40)-(+6)
=13+7+20+40-6
=74;
(4)(-7)-(+5)+(+3)-(-9)
=-7-5+3+9
=-12+12
=0;
(5)18-6÷(-2)×(-
)
=18+3×(-
)
=18-1
=17;
(6)(-4)2×[-
+(-
)]
=16×(-
)
=-22.
| 1 |
| 2 |
=4-3+8×
| 1 |
| 8 |
=4-3+5
=6;
(2)(-5)3×(-
| 3 |
| 5 |
| 5 |
| 4 |
=-125×(-
| 3 |
| 5 |
| 5 |
| 4 |
=75-10
=65;
(3)13+(+7)-(-20)-(-40)-(+6)
=13+7+20+40-6
=74;
(4)(-7)-(+5)+(+3)-(-9)
=-7-5+3+9
=-12+12
=0;
(5)18-6÷(-2)×(-
| 1 |
| 3 |
=18+3×(-
| 1 |
| 3 |
=18-1
=17;
(6)(-4)2×[-
| 3 |
| 4 |
| 5 |
| 8 |
=16×(-
| 11 |
| 8 |
=-22.
点评:本题考查的是有理数的运算能力.注意:
(1)要正确掌握运算顺序,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;
(2)去括号法则:--得+,-+得-,++得+,+-得-.
(1)要正确掌握运算顺序,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;
(2)去括号法则:--得+,-+得-,++得+,+-得-.
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