Elitmus
Exam
General Ability
General Knowledge
how many values of c in the equation x^2-5x+c=0 results in rational roots which are integers?
Read Solution (Total 4)
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- The value of x can be calculated as:
x=( 5 +- sqrt(5^2 -4c))/2
For c = 0 , 4 , 6 , -6, -14, -24 , -36, -50 ……….and so on we can get rational roots which are
Integers.
Hence the Answer is :- Infinite - 9 years agoHelpfull: Yes(10) No(2)
- Since leading coefficient is one and coefficient of x is integer i.e -5 so for every integral value of 'c' for which equation has rational roots. then these rational roots must be integral.
and c is of the form given by
25 - 4c = (2*n +_ 1)^2
c =( 25 - (2*n +_ 1)^2)/4
n belongs to integer
so there exists "Infinitely" many c !! - 9 years agoHelpfull: Yes(2) No(1)
- will u plz explain????? santosh uplawdiya
- 9 years agoHelpfull: Yes(0) No(1)
- Please explain in detail
- 9 years agoHelpfull: Yes(0) No(0)
Elitmus Other Question
Does the questions posted here get repeated in elitmus exams?
if v,w,x,y,z are non negative integer, each less than 11,then how many distinct combinations(w,v,x,y,z) satisfy v(11^4)+w(11^3)+x(11^2)+y(11)+z=151001.
optn
a)0
b)1
c)2
d)3