题目内容
请你先认真阅读材料:
计算(-
)÷(
-
+
-
)
解法1:
(-
)÷(
-
+
-
)
=(-
)÷[(
+
)-(
+
)]
=(-
)÷(
-
)
=(-
)÷
=-
×3
=-
解法2:
原式的倒数为:
(
一
+
-
)÷(-
)
=(
-
+
-
)×(-30)
=-20+3-5+12
=(-20-5)+(3+12)
=-10
再根据你对所提供材料的理解,选择合适的方法计算:
(-
)÷(
-
+
-
).
计算(-
| 1 |
| 30 |
| 2 |
| 3 |
| 1 |
| 10 |
| 1 |
| 6 |
| 2 |
| 5 |
解法1:
(-
| 1 |
| 30 |
| 2 |
| 3 |
| 1 |
| 10 |
| 1 |
| 6 |
| 2 |
| 5 |
=(-
| 1 |
| 30 |
| 2 |
| 3 |
| 1 |
| 6 |
| 1 |
| 10 |
| 2 |
| 5 |
=(-
| 1 |
| 30 |
| 5 |
| 6 |
| 1 |
| 2 |
=(-
| 1 |
| 30 |
| 1 |
| 3 |
=-
| 1 |
| 30 |
=-
| 1 |
| 10 |
解法2:
原式的倒数为:
(
| 2 |
| 3 |
| 1 |
| 10 |
| 1 |
| 6 |
| 2 |
| 5 |
| 1 |
| 30 |
=(
| 2 |
| 3 |
| 1 |
| 10 |
| 1 |
| 6 |
| 2 |
| 5 |
=-20+3-5+12
=(-20-5)+(3+12)
=-10
再根据你对所提供材料的理解,选择合适的方法计算:
(-
| 1 |
| 42 |
| 1 |
| 6 |
| 3 |
| 14 |
| 2 |
| 3 |
| 2 |
| 7 |
原式的倒数为:
(
-
+
-
)÷(-
)
=(
-
+
-
)×(-42)
=-7+9-28+12
=-14.
∴原式=-
.
(
| 1 |
| 6 |
| 3 |
| 14 |
| 2 |
| 3 |
| 2 |
| 7 |
| 1 |
| 42 |
=(
| 1 |
| 6 |
| 3 |
| 14 |
| 2 |
| 3 |
| 2 |
| 7 |
=-7+9-28+12
=-14.
∴原式=-
| 1 |
| 14 |
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