### Usar este ejemplo como base para resolver el problema completo. 


```python
from sympy import *
from sympy import init_printing; init_printing(use_latex = 'mathjax')
```


```python
var('x l m hbar')
```




$$\left ( x, \quad l, \quad m, \quad \hbar\right )$$




```python
f_1 = x*(l - x)
```


```python
f_1
```




$$x \left(l - x\right)$$




```python
diff(f_1, x, 2)
```




$$-2$$




```python
integrando = (-hbar**2/(2*m))*f_1*diff(f_1, x, 2)
integrando
```




$$\frac{\hbar^{2} x}{m} \left(l - x\right)$$




```python
H_11 = Integral(integrando, (x, 0, l))
```


```python
H_11.doit()
```




$$\frac{\hbar^{2} l^{3}}{6 m}$$




```python
s_11 = integrate(f_1**2, (x,0,l))
s_11
```




$$\frac{l^{5}}{30}$$




```python

```

4ff04412901b2c0ece8e16df6940858807669356
ipynb
Jupyter Notebook
Huckel_M0/Huckel_Variatonal_example.ipynb
lazarusA/Density-functional-theory
c74fd44a66f857de570dc50471b24391e3fa901f
MIT
Huckel_M0/Huckel_Variatonal_example.ipynb
lazarusA/Density-functional-theory
c74fd44a66f857de570dc50471b24391e3fa901f
MIT
Huckel_M0/Huckel_Variatonal_example.ipynb
lazarusA/Density-functional-theory
c74fd44a66f857de570dc50471b24391e3fa901f
MIT
Qwen/Qwen-72B
1. YES
2. YES