Respuesta :

Answer:

[tex]A(t) = \pi (0.5 + 2t)^2[/tex]

Step-by-step explanation:

Given

[tex]r(t) = 0.5 + 2t[/tex]

[tex]A(r) = \pi r^2[/tex]

Required

Determine composite function to find A in terms of t

The interpretation of this question is to determine A(t) and this is solved as follows:

Because:

[tex]r(t) = 0.5 + 2t[/tex]

And we want to eliminate r in [tex]A(r) = \pi r^2[/tex]

We have to substitute 0.5 + 2t for r in [tex]A(r) = \pi r^2[/tex]

[tex]A(r) = \pi r^2[/tex]  becomes

[tex]A(t) = \pi (0.5 + 2t)^2[/tex]

The solution can be solved further, but it is best left in this form:

[tex]A(t) = \pi (0.5 + 2t)^2[/tex]