Partial Derivatives Z Aadee1
1. **State the problem:**
We have a function $$Z = e^x \sin y$$ where $$x = u v^2$$ and $$y = v u^2$$.
We need to find the partial derivatives $$\frac{\partial Z}{\partial u}$$ and $$\frac{\partial Z}{\partial v}$$ at $$u=1$$ and $$v=\frac{\pi}{2}$$.
2. **Recall the chain rule for partial derivatives:**
Since $$Z$$ depends on $$x$$ and $$y$$, which in turn depend on $$u$$ and $$v$$, we use:
$$\frac{\partial Z}{\partial u} = \frac{\partial Z}{\partial x} \frac{\partial x}{\partial u} + \frac{\partial Z}{\partial y} \frac{\partial y}{\partial u}$$
$$\frac{\partial Z}{\partial v} = \frac{\partial Z}{\partial x} \frac{\partial x}{\partial v} + \frac{\partial Z}{\partial y} \frac{\partial y}{\partial v}$$
3. **Calculate partial derivatives of $$Z$$ with respect to $$x$$ and $$y$$:**
$$\frac{\partial Z}{\partial x} = e^x \sin y$$
$$\frac{\partial Z}{\partial y} = e^x \cos y$$
4. **Calculate partial derivatives of $$x$$ and $$y$$ with respect to $$u$$ and $$v$$:**
$$x = u v^2 \Rightarrow \frac{\partial x}{\partial u} = v^2, \quad \frac{\partial x}{\partial v} = 2 u v$$
$$y = v u^2 \Rightarrow \frac{\partial y}{\partial u} = 2 u v, \quad \frac{\partial y}{\partial v} = u^2$$
5. **Evaluate all derivatives at $$u=1$$ and $$v=\frac{\pi}{2}$$:**
$$x = 1 \times \left(\frac{\pi}{2}\right)^2 = \frac{\pi^2}{4}$$
$$y = \frac{\pi}{2} \times 1^2 = \frac{\pi}{2}$$
$$\frac{\partial x}{\partial u} = \left(\frac{\pi}{2}\right)^2 = \frac{\pi^2}{4}$$
$$\frac{\partial x}{\partial v} = 2 \times 1 \times \frac{\pi}{2} = \pi$$
$$\frac{\partial y}{\partial u} = 2 \times 1 \times \frac{\pi}{2} = \pi$$
$$\frac{\partial y}{\partial v} = 1^2 = 1$$
6. **Calculate $$\frac{\partial Z}{\partial x}$$ and $$\frac{\partial Z}{\partial y}$$ at these values:**
$$\frac{\partial Z}{\partial x} = e^{\frac{\pi^2}{4}} \sin \left(\frac{\pi}{2}\right) = e^{\frac{\pi^2}{4}} \times 1 = e^{\frac{\pi^2}{4}}$$
$$\frac{\partial Z}{\partial y} = e^{\frac{\pi^2}{4}} \cos \left(\frac{\pi}{2}\right) = e^{\frac{\pi^2}{4}} \times 0 = 0$$
7. **Compute $$\frac{\partial Z}{\partial u}$$:**
$$\frac{\partial Z}{\partial u} = e^{\frac{\pi^2}{4}} \times \frac{\pi^2}{4} + 0 \times \pi = \frac{\pi^2}{4} e^{\frac{\pi^2}{4}}$$
8. **Compute $$\frac{\partial Z}{\partial v}$$:**
$$\frac{\partial Z}{\partial v} = e^{\frac{\pi^2}{4}} \times \pi + 0 \times 1 = \pi e^{\frac{\pi^2}{4}}$$
**Final answers:**
$$\boxed{\frac{\partial Z}{\partial u} = \frac{\pi^2}{4} e^{\frac{\pi^2}{4}}, \quad \frac{\partial Z}{\partial v} = \pi e^{\frac{\pi^2}{4}}}$$