问题 解答题
计算题:
(1)(
3
)2-
16
+
3-8
+
(-2)2

(2)|
2
-
3
|-|2-
3
|-|
3
-1|

(3)(x+1)(x-5)+4(x-1)
(4)(a+b-c)(a-b+c)
答案

(1)原式=3-4-2+2

=-1;

(2)原式=

3
-
2
-(2-
3
)-(
3
-1)

=

3
-
2
-2+
3
-
3
+1

=

3
-
2

-1;

(3)原式=x2-5x+x-5+4x-4

=x2-9;

(4)原式=[a+(b-c)][a-(b-c)]

=a2-(b-c)2

=a2-(b2-2bc+c2

=a2-b2+2bc-c2

多选题
选择题