If m is a natural such that m≤5, then the probability that the quadratic equation x2+mx+12+m2=0 has real roots is
3/5
Discriminant D of the quadratic equation
x2+mx+12+m2=0
is given by
D=m2−4(12+m2)=m2−2m−2=(m−1)2−3Now, D≥0⇔(m−1)2≥3
This is possible for m=3, 4 and 5. Also, the total number of ways of choosing m is 5.
∴ Probability of the required event= 3/5.