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计算与化简:(1)化简18−(π−1)0−412+12(2−1);(2)计算:(x-8y)(x-y).

题目详情
计算与化简:
(1)化简
18
−(π−1)0−4
1
2
+
1
2
(
2
−1);
(2)计算:(x-8y)(x-y).
▼优质解答
答案和解析
(1)原式=3
2
-1-2
2
+
2
2
-
1
2

=
3
2
2
-
3
2


(2)(x-8y)(x-y)
=x2-xy-8xy+8y2
=x2-9xy+8y2