IIT JAM

follow

Top Resources

Snehasish Ghosh posted an Question

July 07, 2020 • 04:33 am

30 points

IIT JAM
Physics (PH)

Please explain how does this x+1 come in this step.

3 Answer(s)

0 Likes
10 Comments
0 Shares

>
Deepak singh 1

this one..
- Likes(1)
- Reply(0)

>
Ghost.

In question you have various powers of x, so you have to put it in a compact form in order to use De-Movire theorm, so they have multiplied both side by (x+1) and as result LHS reduce to the desired form . i am not familiar with any specific rule which you can use everytime to know what to multiple to make equation compact, but i guess it is totally intuitive and observation. Hit and trial Wishes
- Likes(0)
- Reply(2)
Is this topics needed for JAM?
- Like(1)
Yes, complex number is included in jam syllabus, You should know De-Movire theorm and its implementation. Wishes
- Like(0)

>
Deepak singh 1

just multiply (x+1) both sides
- Likes(1)
- Reply(4)
why?
- Like(0)
I am not getting the reason why to multiply x+1 and not any other factor
- Like(0)
firstly by multiplying both side by (x+1) , value of x can be easily find out , please see attached
- Like(0)
u can mulltiply by other factor also , by which u can solve for x , any doubt please ask
- Like(0)

>
Chandra prakash

actually u have to ask about x+1 factor.. and how to come in that case bcoz if u are adding a term like x+1 then after that u have to remove one soluation of x.. best regards
- Likes(1)
- Reply(4)
see
- Like(0)
see
- Like(0)
see
- Like(0)
go through the link , attached by ma'am
- Like(0)

>
Dhairya sharma Best Answer

https://images.app.goo.gl/EENXvrjL5DGS8oQy5 go through it
- Likes(1)
- Reply(4)
it will help you definitely
- Like(1)
see this
- Like(1)
👍
- Like(1)
👍
- Like(1)

>
Dhairya sharma

same like this
- Likes(1)
- Reply(4)
like we did it
- Like(1)
Ma'am, but here they have said to use De Moivre's theorem
- Like(1)
hope all those helped u
- Like(1)
👍
- Like(1)

>
Ruby negi

but remember that as u add x+1, u are adding a x=-1 so after doing solution , u have to remove one solution of x...
- Likes(1)
- Reply(2)
Ma'am, if the question is x^9 -x^5+ x^4 -1 =0 ,then?
- Like(0)
What should we add?
- Like(0)

>
Dhairya sharma

if it satisfies the equation then x+1 will be one root of the equation. now we will furtger devide the whole equation with it
- Likes(1)
- Reply(0)

>
Dhairya sharma

because x = -1 will satisfy the equation so
- Likes(1)
- Reply(1)
Ma'am, but x= -1 does not satisfy the equation
- Like(1)

>
Ruby negi

they add it just for making the question easy.. by adding x+1 u get formula of x^5+1...
- Likes(1)
- Reply(1)
see this
- Like(0)

T