1. **Problem Statement:**
We need to find the Laplace Transform of the CPU load function:
$$f(t) = \begin{cases} t^3 & m+1 < t < m+2 \\ 4 - t^2 & m+2 < t < m+4 \\ 1 & \text{otherwise} \end{cases}$$
where $m$ is the last digit of the student ID. Given student ID ends with 6, so $m=6$.
2. **Rewrite the function with $m=6$:**
$$f(t) = \begin{cases} t^3 & 7 < t < 8 \\ 4 - t^2 & 8 < t < 10 \\ 1 & \text{otherwise} \end{cases}$$
3. **Laplace Transform definition:**
$$\mathcal{L}\{f(t)\} = \int_0^\infty e^{-st} f(t) dt$$
4. **Break the integral into intervals:**
$$\mathcal{L}\{f(t)\} = \int_0^7 e^{-st} \cdot 1 \, dt + \int_7^8 e^{-st} t^3 \, dt + \int_8^{10} e^{-st} (4 - t^2) \, dt + \int_{10}^\infty e^{-st} \cdot 1 \, dt$$
5. **Calculate each integral separately:**
**Integral 1:**
$$I_1 = \int_0^7 e^{-st} dt = \left[-\frac{e^{-st}}{s}\right]_0^7 = \frac{1 - e^{-7s}}{s}$$
**Integral 2:**
$$I_2 = \int_7^8 e^{-st} t^3 dt$$
Use integration by parts repeatedly or known formula for $\int t^n e^{-st} dt$.
Set $I_n = \int t^n e^{-st} dt$. Using reduction formula:
$$I_n = -\frac{t^n e^{-st}}{s} + \frac{n}{s} I_{n-1}$$
Calculate stepwise:
- For $n=3$:
$$I_3 = -\frac{t^3 e^{-st}}{s} + \frac{3}{s} I_2$$
- For $n=2$:
$$I_2 = -\frac{t^2 e^{-st}}{s} + \frac{2}{s} I_1$$
- For $n=1$:
$$I_1 = -\frac{t e^{-st}}{s} + \frac{1}{s} I_0$$
- For $n=0$:
$$I_0 = \int e^{-st} dt = -\frac{e^{-st}}{s}$$
Substitute back:
$$I_1 = -\frac{t e^{-st}}{s} - \frac{1}{s^2} e^{-st}$$
$$I_2 = -\frac{t^2 e^{-st}}{s} + \frac{2}{s} \left(-\frac{t e^{-st}}{s} - \frac{1}{s^2} e^{-st}\right) = -\frac{t^2 e^{-st}}{s} - \frac{2 t e^{-st}}{s^2} - \frac{2 e^{-st}}{s^3}$$
$$I_3 = -\frac{t^3 e^{-st}}{s} + \frac{3}{s} \left(-\frac{t^2 e^{-st}}{s} - \frac{2 t e^{-st}}{s^2} - \frac{2 e^{-st}}{s^3}\right) = -\frac{t^3 e^{-st}}{s} - \frac{3 t^2 e^{-st}}{s^2} - \frac{6 t e^{-st}}{s^3} - \frac{6 e^{-st}}{s^4}$$
Evaluate $I_3$ from 7 to 8:
$$I_2 = \left[ I_3 \right]_7^8 = \left(-\frac{t^3 e^{-st}}{s} - \frac{3 t^2 e^{-st}}{s^2} - \frac{6 t e^{-st}}{s^3} - \frac{6 e^{-st}}{s^4}\right) \Bigg|_7^8$$
6. **Integral 3:**
$$I_3 = \int_8^{10} e^{-st} (4 - t^2) dt = 4 \int_8^{10} e^{-st} dt - \int_8^{10} t^2 e^{-st} dt$$
Calculate each part:
- $$\int_8^{10} e^{-st} dt = \left[-\frac{e^{-st}}{s}\right]_8^{10} = \frac{e^{-8s} - e^{-10s}}{s}$$
- For $$\int t^2 e^{-st} dt$$ use formula from above:
$$I_2 = -\frac{t^2 e^{-st}}{s} - \frac{2 t e^{-st}}{s^2} - \frac{2 e^{-st}}{s^3}$$
Evaluate from 8 to 10:
$$\left[ I_2 \right]_8^{10} = \left(-\frac{t^2 e^{-st}}{s} - \frac{2 t e^{-st}}{s^2} - \frac{2 e^{-st}}{s^3}\right) \Bigg|_8^{10}$$
So,
$$I_3 = 4 \cdot \frac{e^{-8s} - e^{-10s}}{s} - \left[ I_2 \right]_8^{10}$$
7. **Integral 4:**
$$I_4 = \int_{10}^\infty e^{-st} dt = \left[-\frac{e^{-st}}{s}\right]_{10}^\infty = \frac{e^{-10s}}{s}$$
8. **Combine all integrals:**
$$\mathcal{L}\{f(t)\} = I_1 + I_2 + I_3 + I_4$$
9. **Final compact expression:**
$$\boxed{\begin{aligned}
\mathcal{L}\{f(t)\} &= \frac{1 - e^{-7s}}{s} + \left(-\frac{t^3 e^{-st}}{s} - \frac{3 t^2 e^{-st}}{s^2} - \frac{6 t e^{-st}}{s^3} - \frac{6 e^{-st}}{s^4}\right) \Bigg|_7^8 \\
&+ 4 \cdot \frac{e^{-8s} - e^{-10s}}{s} - \left(-\frac{t^2 e^{-st}}{s} - \frac{2 t e^{-st}}{s^2} - \frac{2 e^{-st}}{s^3}\right) \Bigg|_8^{10} + \frac{e^{-10s}}{s}
\end{aligned}}$$
This expression fully represents the Laplace Transform of the given piecewise function with $m=6$.
**Note:** For handwritten submission, write each step carefully showing the integration by parts and evaluation at limits.
Laplace Transform 014436
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