Question

Harlie uses the function f(x) = 2x2 + 5x + 3 to track the temperature of a substance, where x represents the time. When you evaluate f(5) you find that the temperature of the substance is 78°

c. What is the domain of the situation of Charlie's quadratic function?

Answer 1

We suspect the domain is values of x greater than 0 but less than about 100. At about x=70, the temperature matches that of the surface of the sun. Some experimental processes may produce higher temperatures, but a practical limit is certain to be x less than 4000, at which point the temperature exceeds the core temperature of the sun.