TCS
Company
How many integers x satisfy the equation
(x^2 - 4x + 5)x^2 + x = 1
3
0
more than 4
4
2
Read Solution (Total 12)
-
- for any values of x, the terms (x^2-4x+5) & x^2 is always positive
also x is an integer so x^2>=x
hence there is no integral soln of given equation.
ANS-0
- 11 years agoHelpfull: Yes(24) No(4)
- ans=4
as x4 - 11 years agoHelpfull: Yes(9) No(6)
- after simplification it is a 4th degree eqn so it has 4 roots
but we have to find integeral value of x,there is no integral root of eqn bcoz in eqn
(x^2 - 4x + 5)x^2 + x = 1
value of (x^2 - 4x + 5) is always +ve for any value of x
so (x^2 - 4x + 5)x^2 >0 for any x(x^2>0)
for any integer (x^2 - 4x + 5)x^2 + x never equals to 1
check for -2,-1,0,1,2 etc
hence there is no integer value of x.
- 11 years agoHelpfull: Yes(7) No(0)
- (x2-4x+5)x2+x=1
x4-4x3+5x2+x-1=0
here we get a fourth order equation.therefore it has 4 roots - 11 years agoHelpfull: Yes(3) No(2)
- if x=1, LHS=3 if x=2 LHS=6 (increasing LHS for increasing x)
if x=-1 LHS=9 if x=-2 LHS=66 (increasing LHS for decreasing x)
and if x=0, LHS=0.
sol. is 0
- 11 years agoHelpfull: Yes(3) No(1)
- i dont get the Question and answer both guys....
- 11 years agoHelpfull: Yes(2) No(2)
- ans= 0
since ( x^2 - 4x+ 5) has imaginary roots. so no integer will satisfy the above mentioned equation - 11 years agoHelpfull: Yes(2) No(1)
- ans is 0 as no integer value is satisfying above eqn
- 11 years agoHelpfull: Yes(2) No(0)
- rakesh kumar pls explain it in details.....
- 11 years agoHelpfull: Yes(2) No(1)
- 4 as after multiplying we get a fourth order eqn which must hav 4 roots
- 11 years agoHelpfull: Yes(1) No(4)
- ans:4
becoz the highest power of x is 4 in given equation - 11 years agoHelpfull: Yes(0) No(1)
- f(x)= x4-4x3+5x2+x-1=0
change in sign 3 so 3 +ve real roots
again f(-x)=x4+4x3+5x2-x-1=0
change in sign =1 so 1 -ve real root so total 4 integer will satisfy the eqn
hence 4 is the ans.....
(if roots are not real they are imaginary not integers so check this out) - 11 years agoHelpfull: Yes(0) No(1)
TCS Other Question