问题 解答题
计算:(1)
a
b+1
+
2a
b+1
-
3a
1+b

(2)
x2+1
x-3
x2-9
x3+x
答案

(1)

a
b+1
+
2a
b+1
-
3a
1+b
=
a+2a-3a
b+1
=0;

(2)

x2+1
x-3
x2-9
x3+x
=
x2+1
x-3
×
(x-3)(x+3)
x(x2+1)
=
x+3
x

故答案为0、

x+3
x

名词解释
填空题