Let us consider the quadratic equation: ax˛ + bx + c = 0.
We assign values to the coefficients a, b and c by throwing a die.
What is the probability that the equation will have real roots ?
If I recall my high school algebra correctly, there were two basic categories of numbers involved in factoring a quadratic equation: imaginary roots (that involve the peculiar concept of the square root of negative 1) and real roots (all others). If the die thrown is normal, it would have the integers 1 through 6 or the six faces. Therefore, the probabily of having real roots is 100%. It is also possible to determine the probability that the roots of the equation are integers, but this would take a bit more work.
G. Steel
Quadratic Equation Coefficients
