Question

The area (A) of a circle is a function of its radius (r) and is given by the function A=f(r)=pie r^2. What is the domain of this function

A. All positive real numbers
B. All real numbers
C. All positive real numbers including 0
D. All real numbers excluding fraction

Answer 1

all positive real numbers. in this function, the domain is the radius. all real numbers includes negative numbers, and u cant have a negative distance. you also cant have a radius of 0 because the circle wouldnt exist. and u can have a fraction domain, so A is the answer