(15 points) A Bernoulli differential equation is one of the form
(dy)/(dx)+P(x)y=Q(x)y^(n)
Observe that, if
n=0
or 1 , the Bernoulli equation is linear. For other values of
n
, the substitution
u=y^(1-n)
transforms the Bernoulli equation into the linear equation
(du)/(dx)+(1-n)P(x)u=(1-n)Q(x)
Consider the initial value problem
xy^(')+y=-5xy^(2),y(1)=-2.
(a) This differential equation can be written in the form
(**)
with
P(x)=
Q(x)=
n=
(b) The substitution
u=
?
will transform it into the linear equation
(du)/(dx)+
?
u=
?
(c) Using the substitution in part (b), we rewrite the initial condition in terms of
x
and
u
:
u(1)=
?
(d) Now solve the linear equation in part (b), and find the solution that satisfies the initial condition in part (c).
u(x)=
?