Q:

Suppose you have a cube of length s. The volume of that cube is V = s^3. Now let's suppose the dimensions of that cube (and hence its volume) depend on time. We are wondering about the relationship between the growth of the length versus the growth of the volume. Supposes(t) = t.Then s'(t) = t______________ and V'(t) = t ___________Next suppose V(t) = t. s'(t) = t______________ and V'(t) = t____________

Accepted Solution

A:
Answer:Part 1s'(t)=1[tex]V'(t)=3t^2[/tex]Part 2[tex]s'(t)=\frac{1}{3\sqrt[3]{t^2}}[/tex]V'(t)=1Step-by-step explanation:As stated in the question, if s is the length of a cube, its volume is [tex]V(s)=s^3[/tex]When s changes in time, the volume will change too. The challenge here is to find the growth of the volume in terms of those changes in length Part 1 [tex]s(t)=t[/tex]The change of s with respect to time is found by differentiating the relation to get [tex]s'=1[/tex]The volume will also change, and its derivative is [tex]V'(s)=3s^2.s'[/tex]Since s'=1 [tex]V'(s)=3s^2[/tex]How s=t [tex]V'(t)=3t^2[/tex]Part 2 [tex]V(t)=t[/tex]Replacing this into the formula for V(s) [tex]V(s)=s^3=t[/tex]So we have [tex]s=\sqrt[3]{t}=t^{\frac{1}{3}}[/tex]Computing the derivatives: V(t)=t => V'(t)=1 [tex]s'(t)=\frac{1}{3}t^{-\frac{2}{3}}=\frac{1}{3\sqrt[3]{t^2}}[/tex]