问题 解答题
计算:
(1)
2a
a+1
+
2
a+1

(2)
y2-4y+4
2y-6
1
y+3
÷
12-6y
9-y2
答案

(1)原式=

2a+2
a+1

=2;

(2)原式=

(y-2)2
2(y-3)
×
1
y+3
÷
6(2-y)
(3-y)(3+y)

=

(y-2)2
2(y-3)(y+3)
×
(3-y)(3+y)
6(2-y)

=

y-2
12

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