Let f be the function that determines the area of a circle (in square cm) that has a radius of r cm. That is, f ( r ) represents the area of a circle (in square cm) that has a radius of r cm. Use function notation to respond to each item below. Represent the area (in square cm) of a circle that has a radius of 4.3 cm.

Explanation:

Functions

When one magnitude depends on other (or others), we usually try to express them as a function which can contain any number of variables, constants, and operations.

The area of a circle is computed by the well-known formula

We are required to use function notation to express the area of a circle f(r) in terms of the radius r. If the radius is in cm, then the area is in .

The required function is

For a radius of 4.3 cm:

The most common difference between the two is that while conductors allow free flow of electrons from one atom to another, insulators restrict free flow of electrons. Conductors allow electrical energy to pass through them, whereas insulators do not allow electrical energy to pass through them.