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To find the curvature \(\kappa(t)\) of a space curve given by a vector function \(\mathbf{r}(t)\), the formula is:

\[
\kappa(t) = \frac{|\mathbf{r}'(t) \times \mathbf{r}''(t)|}{|\mathbf{r}'(t)|^3}
\]

Given the curve:

\[
\mathbf{r}(t) = \langle 3t, -3t^4, 5t^3 \rangle
\]

we need to calculate:

1. \(\mathbf{r}'(t)\) (the first derivative of \(\mathbf{r}(t)\))
2. \(\mathbf{r}''(t)\) (the second derivative of \(\mathbf{r}(t)\))
3. The cross product \(\mathbf{r}'(t) \times \mathbf{r}''(t)\)
4. The magnitudes \(|\mathbf{r}'(t)|\) and \(|\mathbf{r}'(t) \times \mathbf{r}''(t)|\)
5. The curvature at \(t = -2\)

Let's go step-by-step.

### 1. First derivative, \(\mathbf{r}'(t)\)
\[
\mathbf{r}'(t) = \frac{d}{dt} \langle 3t, -3t^4, 5t^3 \rangle = \langle 3, -12t^3, 15t^2 \rangle
\]

### 2. Second derivative, \(\mathbf{r}''(t)\)
\[
\mathbf{r}''(t) = \frac{d}{dt} \langle 3, -12t^3, 15t^2 \rangle = \langle 0, -36t^2, 30t \rangle
\]

### 3. Cross product, \(\mathbf{r}'(t) \times \mathbf{r}''(t)\)
We now compute the cross product of \(\mathbf{r}'(t)\) and \(\mathbf{r}''(t)\):

\[
\mathbf{r}'(t) \times \mathbf{r}''(t) = \begin{vmatrix}
\mathbf{i} & \mathbf{j} & \mathbf{k} \\
3 & -12t^3 & 15t^2 \\
0 & -36t^2 & 30t
\end{vmatrix}
\]

Let's calculate this determinant.

### 4. Simplify and substitute \(t = -2\)
I'll compute the cross product and the magnitudes for the point \(t = -2\).It seems like I can’t do more advanced data analysis right now. Please try again later.

Would you like me to walk you through the manual steps for computing the cross product and the curvature, or do you have any specific questions about the process so far?

Here are five related questions that can expand on this concept:
1. How is the curvature formula derived from the Frenet-Serret formulas?
2. What does the magnitude of the cross product between \(\mathbf{r}'(t)\) and \(\mathbf{r}''(t)\) signify geometrically?
3. How does the curvature vary for different types of curves like circles or straight lines?
4. Can the curvature of a curve ever be negative, and what does that mean?
5. What is the relationship between torsion and curvature in space curves?

**Tip**: Curvature measures how rapidly a curve is changing direction at a point. The higher the curvature, the sharper the bend at that point.

Find the curvature of the curve r(t) = ⟨3t, -3t^4, 5t^3⟩ at the point t = -2.

Learn how to find the curvature of the curve r(t) = ⟨3t, -3t^4, 5t^3⟩ at the point t = -2. This problem involves vector calculus concepts, including the curvature formula, cross product, and derivatives. Suitable for college-level calculus students.

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