The length of a rectangle is 5 in. more than 3 times its width. The quadratic function f(x) = x(3x + 5) represents the area of the rectangle in terms of its width. What is a reasonable domain of the function?A) real numbers B) all real numbers less than 50 C) all real numbers less than zero D) all real numbers greater than zero
Accepted Solution
A:
f(x)=x(3x+5) or f(x)=3x²+5x Here the domain in general is: -∞<x<∞ But the length of the rectangle cannot be negative, therefore the domain is all real numbers greater than zero.