35道.

题目

35道.
符号^代表平方.读起来就是（X的平方）.
1,x^-x-20
2,x^-9x+20
3,x^-9x-20
4,x^+9x+20
5,x^-18x+32
6,x^+14x-31
7,x^+18x+32
8,x^+14x-32
9,x^+19x+48
10,x^+47x-48
11,x^+13x-48
12,x^+2x-48
13,x^+26x+48
14,x^-22x-48
15,x^+17x+72
16,x^+21x-100
17,x^-x-72
18,x^-17x+72
19,x^+6x+8
20,x^-11x+28
21,x^-9x+8
22,x^+4x-12
23,x^-2x-15
24,x^+6x+5
25,a^+a-12
26,x^-8x+7
27,x^+5x-14
28,x^-3x-28
29,x^-3x-10
30,n^-14n+24
31,x^-7x+12
32,x^-7x+6
33,x^-x-6
34,x^+3x-10
35,x^+2x-15

答案

1,x^-x-20 =(x-5)(x+4)
2,x^-9x+20 =(x-5)(x-4)
3,x^-9x-20 =(x-3+根号14）（x-3-根号14)
4,x^+9x+20 =(x+5)(x+4)
5,x^-18x+32 =(x-2)(x-16)
6,x^+14x-31
7,x^+18x+32
8,x^+14x-32
9,x^+19x+48
10,x^+47x-48
11,x^+13x-48
12,x^+2x-48
13,x^+26x+48
14,x^-22x-48
15,x^+17x+72
16,x^+21x-100
17,x^-x-72
18,x^-17x+72
19,x^+6x+8
20,x^-11x+28
21,x^-9x+8
22,x^+4x-12
23,x^-2x-15
24,x^+6x+5
25,a^+a-12
26,x^-8x+7
27,x^+5x-14
28,x^-3x-28
29,x^-3x-10
30,n^-14n+24
31,x^-7x+12
32,x^-7x+6
33,x^-x-6
34,x^+3x-10
35,x^+2x-15