Suppose f(x)=x^3+ax^2+bx+c.Now a,b,c, are chosen respectively by throwing a dice 3 times.Find the probability that f(x) is an increasing function.

• 5/12..is the ans.
  we can see this way.
  for an increasing function its derivative must be positive.
  and here dF/dx=3x^2+2ax+b
  since, dF/dx >0;
  for this its discriminant (D)
• 11 years agoHelpfull: Yes(6) No(2)
• 1/2 is the answer
• 11 years agoHelpfull: Yes(1) No(9)
• I think the answer is one because a,b, c can take value ranging from 1-6, there is no option of the number being negative. So the function will always be an increasing function. So probability is 1.
• 11 years agoHelpfull: Yes(1) No(6)