Home » Ask & Discuss » Mathematics. » Algebra « Back to Discussion

Algebra

New kid on the Block

Joined:	18 May 2011
Post:	18

18 May 2011 20:04:36 IST

0 People liked this

449

no. of distinct real solutions of the equation x(x^2-1)(x+2)+1=0

None

no. of distinct real solutions of the equation x(x^2-1)(x+2)+1=0

Share this article on:

Comments (7)

NugoRama

Blazing goIITian

Joined: 11 Mar 2009

Posts: 5517

18 May 2011 22:45:12 IST

Like 0 people liked this

manisha jajoo

Scorching goIITian

Joined: 2 Mar 2011

Posts: 216

19 May 2011 14:19:45 IST

Like 0 people liked this

is it 2

Yagyank

New kid on the Block

Joined: 18 May 2011

Posts: 18

19 May 2011 17:35:46 IST

Like 0 people liked this

How you guys got the answer?

Inferno

Blazing goIITian

Joined: 19 Apr 2010

Posts: 359

19 May 2011 18:23:45 IST

Like 1 people liked this

x(x^2-1)(x+2)+1=0

x(x+1)(x-1)(x+2)+1=0

(x^2+x)(x^2+x-2)+1=0

Put (x^2+x)=u

u(u-2)+1=0

u^2-2u+1=0

u=1

x^2+x=1

x^2+x-1=0

x=[(-1)+-(5^(1/2))]/2

Hence 2 real values.

Are you from Brilliant Tutorials.

Yagyank

New kid on the Block

Joined: 18 May 2011

Posts: 18

19 May 2011 18:30:24 IST

Like 0 people liked this

Yes inferno i am from brilliant tutorials i also thought that answer is 2 i just wnated to check thank you :)

and can you please tell me your name

Inferno

Blazing goIITian

Joined: 19 Apr 2010

Posts: 359

20 May 2011 06:25:05 IST

Like 0 people liked this

I am also from Brilliant Tutorials. If you have more doubts then after posting them do nudge me once.
And one more big thing that you did not know. The solutions,SOLUTIONS,SSOOLLUUTTIIOONNSS to the WNICE are online. Also I did not copy my answer from there. It's my own solution. There also the same procedure is followed. So, don't doubt me.
What will you do with my name. We don't know each other.

hemang

Blazing goIITian

Joined: 27 Dec 2010

Posts: 1474

20 May 2011 09:43:10 IST

Like 0 people liked this

two is the answer.

Quick Reply

Reply

	Some HTML allowed.
	Keep your comments above the belt or risk having them deleted.
	Signup for a avatar to have your pictures show up by your comment
	If Members see a thread that violates the Posting Rules, bring it to the attention of the Moderator Team