Answer:
To find the differentials, we must derivate:
a) y = s/(1 + 5s)
remember that when we have a function:
f(x) = h(x)*g(x)
we have that the differentiation rule is:
f'(x) = h'(x)*g(x) + h(x)*g'(x)
using this rule, we have:
Then te differential is:
b) now the function is:
y = e^(-u)*cos(u)
We use the same rule as before for the derivation:
Then we have: