Question

The area of a circle can be represented by the function A[r]=pie, r squared with domain r≥0, where r
is the radius of the circle. Which statement about this function is true? A.
The function has a minimum.

B.
The function has two zeros.

C.
The function has no zeros.

D.
The function has a maximum.

Answer 1

A. The function has a minimum.

Reason: A(r) = πr^2 ≥ 0 for r ≥ 0 and attains its smallest value 0 at r = 0, so it has a minimum. It has one zero (r = 0), not two, and no maximum (it grows without bound as r → ∞).