有没有好办法？

The quadratic polynomial f(x) has a zero at x=2. The polynomial f(f(x)) has only one real zero at x=5. Compute f(0).

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• 回复：有没有好办法？ -jinjing- ♀ (92 bytes) () 07/11/2011 postreply 13:37:17

• 回复：回复：有没有好办法？ -cma- ♂ (57 bytes) () 07/11/2011 postreply 14:36:14

• 回复：回复：回复：有没有好办法？ -jinjing- ♀ (267 bytes) () 07/11/2011 postreply 15:07:34

• 回复：回复：回复：回复：有没有好办法？ -cma- ♂ (111 bytes) () 07/11/2011 postreply 15:21:06

• If they are not both 0, 5 is not only one root. -jinjing- ♀ (0 bytes) () 07/12/2011 postreply 07:11:08

• [a*3*(5-b)-2]=0 or [a*3*(5-b)-b)]=0.It can't get answer.Only bot -jinjing- ♀ (61 bytes) () 07/12/2011 postreply 10:37:39

• 5 -乱弹- ♂ (0 bytes) () 07/12/2011 postreply 20:13:46

• 愿闻其详. -jinjing- ♀ (0 bytes) () 07/13/2011 postreply 05:18:53

• 不知道答案，但可列两个方程。 -乱弹- ♂ (0 bytes) () 07/12/2011 postreply 20:17:43

• 回复：有没有好办法？ -康MM- ♀ (91 bytes) () 07/13/2011 postreply 16:49:19

• 回复：回复：有没有好办法？ -15少- ♂ (155 bytes) () 07/14/2011 postreply 06:57:08

• 回复：回复：回复：有没有好办法？ -康MM- ♀ (72 bytes) () 07/14/2011 postreply 08:43:07

• Please explain. -15少- ♂ (0 bytes) () 07/14/2011 postreply 10:22:52

• if change to -15少- ♂ (201 bytes) () 07/14/2011 postreply 10:26:58

• 回复：回复：回复：回复：有没有好办法？ -康MM- ♀ (105 bytes) () 07/14/2011 postreply 12:01:02

• good -15少- ♂ (0 bytes) () 07/14/2011 postreply 13:24:29

• Why? if f(8)=0,b=8? -jinjing- ♀ (0 bytes) () 07/15/2011 postreply 21:06:13

• Assume f(x)'s coefficients are all real; -乱弹- ♂ (274 bytes) () 07/13/2011 postreply 16:56:53

• 回复：Assume f(x)'s coefficients are all real; -jinjing- ♀ (247 bytes) () 07/13/2011 postreply 20:37:56

• Did not read this before send my post, which is the same. -wxcfan123- ♂ (0 bytes) () 07/15/2011 postreply 16:41:21

• Dear mca,I'm sorry, my answer is wrong as misunderstanding the Q -jinjing- ♀ (0 bytes) () 07/14/2011 postreply 06:05:12

• -32/9 -15少- ♂ (286 bytes) () 07/14/2011 postreply 06:40:13

• two solutions:-32/9 and -128/9. -jinjing- ♀ (0 bytes) () 07/14/2011 postreply 10:42:34

• no sir! -15少- ♂ (0 bytes) () 07/14/2011 postreply 11:29:04

• yes,b=2,OK,b=8,fof has 5,5+(-)3SQUAT3/2,3roots.not good. -jinjing- ♀ (34 bytes) () 07/14/2011 postreply 16:43:38

• follow jinjing -wxcfan123- ♂ (364 bytes) () 07/15/2011 postreply 10:28:27

• 谢谢您给我打气, -jinjing- ♀ (119 bytes) () 07/15/2011 postreply 11:13:27

• 回复：谢谢您给我打气, -wxcfan123- ♂ (234 bytes) () 07/15/2011 postreply 14:13:18

• If you solve a from I, should prove II does not have real root, -wxcfan123- ♂ (0 bytes) () 07/15/2011 postreply 14:41:19

• Wrong way is always as wrong reason. -jinjing- ♀ (152 bytes) () 07/15/2011 postreply 15:21:12

• Math is not riddle -15少- ♂ (655 bytes) () 07/15/2011 postreply 15:20:39

• 回复：Math is not riddle -jinjing- ♀ (273 bytes) () 07/15/2011 postreply 16:03:10

• Why make stupid calcul when -15少- ♂ (815 bytes) () 07/15/2011 postreply 17:33:47

• You totally misunderstanding me, f(x)=a(X-5)^2+b,why b=2? you te -jinjing- ♀ (37 bytes) () 07/15/2011 postreply 18:04:50

• you tell me,please,not 8. -jinjing- ♀ (0 bytes) () 07/15/2011 postreply 18:07:08

• Ms. Kang has explained, her explanation is not as clear as you d -15少- ♂ (461 bytes) () 07/16/2011 postreply 06:30:03

• Why f(8)=0?Cs we use a Thm, It is unknow for most people here. -jinjing- ♀ (493 bytes) () 07/16/2011 postreply 08:19:30

• You like calcul -15少- ♂ (329 bytes) () 07/16/2011 postreply 09:10:20

• 回复：You totally misunderstanding me, f(x)=a(X-5)^2+b,why b=2? you -15少- ♂ (1365 bytes) () 07/16/2011 postreply 06:09:01

• cma,where have you been? Following is my solution for you, -jinjing- ♀ (330 bytes) () 07/15/2011 postreply 18:57:47

• An elegant way to get jingin's wrong answer 8/9 -15少- ♂ (634 bytes) () 07/16/2011 postreply 08:52:07