In [14]:
import numpy as np
def sigmoid(x):
    return 1.0 / ( 1.0 + np.exp(-x) )

q 3


In [20]:
sigmoid(1.5)


Out[20]:
0.81757447619364365

In [21]:
h0=sigmoid( (0.5 * 9) - 1)

In [22]:
h1=sigmoid( ((0.5 * 4) - 1) - h0 )

In [23]:
z1 = h1 * (-0.7)

In [24]:
y1 = sigmoid(z1)
y1


Out[24]:
0.4121391408076901

q 4


In [12]:
np.exp(0.2) / (1+ np.exp(0.2))**2


Out[12]:
0.24751657271186001