1
Athenes Analyst
·2012-04-11 03:04:02
Roots can be 0 and 1 only.
So combinations may be (0,0) ; (1,1) ; (0,1).
So probably 3.
Sorry I am not thinking that much
262
Aditya Bhutra
·2012-04-11 05:37:02
let the roots be x,y
thus on sqarring , roots are x2,y2
there are two possibilities ,
x=x2 and y=y2
x=0,1 y=0,1 (3 solns.)
other possibility ,
x=y2 y=x2
or x = x4 and y=y4
x(x3-1)=0 and y(y3-1)=0
x=0,1,ω,ω2 y=0,1,ω,ω2
thus all solns. are ,
(1,1)
(1,0)
(0,0)
(ω,ω2)
Ans:4
1
Athenes Analyst
·2012-04-11 19:56:48
aditya you want to say ω=ω2.
On squaring ω we dont get the same answer.
262
Aditya Bhutra
·2012-04-12 01:15:56
(ω,ω2)
on squarring ,
(ω2,ω)
same roots , thus same equation.
1
Athenes Analyst
·2012-04-12 09:04:56
Thanks Aditya.... Silly me :D
11
Devil
·2012-04-12 23:35:08
A couple of points:
Firstly for a Quadratic to remain unchanged its coefficients must be unchanged...
Σx2=Σx and Πx=Πx2
So that gives (x+y)=2,-1 with xy=±1
So altogether 4 such equations (It is unnecessary to get the solutions)
Secondly I doubt whether the list of solutions that Aditya has given is exhaustive. I think there are a couple of more solutions (provided I haven't screwed up my calculations again)
262
Aditya Bhutra
·2012-04-13 04:41:58
plz disclose the "couple of more solutions" . (because i am not getting any)