c consists of only non negative numbers in the given equation x^2 - 7x + c =0 how many rational roots occurs
a.) 1 b.) 4 c.) 6 d.) infinite

• in question something is missing that is c is also real non negative numberd 49-4c for finding the value of roots of this equation (49-4c)^1/2 has to rational integerso only c=0,6,10,12 hence b)4 is correct answer.
• 9 years agoHelpfull: Yes(24) No(3)
• ans is d.
  
• 9 years agoHelpfull: Yes(16) No(3)
• In question they are asking only how many rational roots and c consists only non negative numbers means whole no.s . So for c=0 , the equation has 2 roots and for c=1 there will be 2 roots and for c=2 there will be 2 roots and for c=3 there will be 2 roots and so on.
  so the equation has infinite roots
• 9 years agoHelpfull: Yes(5) No(5)
• for rational root D=perfect squre here D=49-4c and also we cant take c(-ve)a/c to question so possible value of c for which root is rational is C=0,6,10,12
  WHERE D=b*b-4ac
• 9 years agoHelpfull: Yes(5) No(0)
• This question was asked in yesterday elitmus test .... one of the simplest
  question
• 9 years agoHelpfull: Yes(3) No(5)
• ans is infinite
• 9 years agoHelpfull: Yes(2) No(1)
• b) 4 is the answer. Vikash is correct. I got this question yesterday in litmus.
• 8 years agoHelpfull: Yes(2) No(0)
• c) 6 rational roots possible
  
• 9 years agoHelpfull: Yes(1) No(3)
• (49-4c)^1/2
  put c=0,6,10,12 we get 2 rational roots distinct each time.
  so total is 8 roots.Pravena please dont give incomplete choices.
  
• 9 years agoHelpfull: Yes(1) No(2)
• there was no option as 8....
• 9 years agoHelpfull: Yes(1) No(0)
• for rational roots D >=0;
  (49-4c)^1/2>=0;
  
  so probable value of c={0,1,2,3,4,5,6,7,8,9,10,11,12}
  
  substituting these value of c one by one we will see at c={0,6,10.12}
  condition gets full fill...so
  Ans should be (b).
• 9 years agoHelpfull: Yes(1) No(0)
• C is the answer
  Put c=6,10,12
  The roots are 1,6,2,5,3 and 4
• 9 years agoHelpfull: Yes(0) No(4)
• Can anyone explain me why it is infinite
• 9 years agoHelpfull: Yes(0) No(1)
• in question something is missingthat isc is also real non negative numberd49-4c for finding the value of roots of this equation49-4c12 has to rational integerso only c061012hence b4 is answer
• 9 years agoHelpfull: Yes(0) No(0)
• @ Amit Anand The choices r not incomplete...
• 9 years agoHelpfull: Yes(0) No(0)
• option b is right
• 9 years agoHelpfull: Yes(0) No(0)
• there should be an additional information regarding c that what type of value shoul it take if it can take +ve real no. then answer should be 8 as c can take values : 0,6,10,12 all together which gives 8 roots otherwise answer will be d infinite
  
• 9 years agoHelpfull: Yes(0) No(0)
• option d is correct
• 9 years agoHelpfull: Yes(0) No(1)
• 49-4*1*c>=0
  =>c
• 9 years agoHelpfull: Yes(0) No(0)
• there will be total of 4 value of c i.e., c=0,6,10,12 which will give rational roots
  as roots= (7+-(49-4c)^1/2) /2 should be rational.
• 9 years agoHelpfull: Yes(0) No(0)