SOLUTION: Find a solution to the initial value problem y′+sin(t)y=g(t), y(0)=7, g(t)= −sin(t),if π < t ≤ 2π. y(t)=___________ __,if π < t ≤ 2π.

Algebra ->  Expressions -> SOLUTION: Find a solution to the initial value problem y′+sin(t)y=g(t), y(0)=7, g(t)= −sin(t),if π < t ≤ 2π. y(t)=___________ __,if π < t ≤ 2π.      Log On


   



Question 1184451: Find a solution to the initial value problem
y′+sin(t)y=g(t), y(0)=7, g(t)= −sin(t),if π < t ≤ 2π.
y(t)=______________,if π < t ≤ 2π.

Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!

I have my doubts on your function g(t), as it is defined on π < t ≤ 2π, but your IVP starts at t = 0,
so there is a bit of an incompatibility between the solution function y(t) and g(t).

If we still push ahead with the solution, the integrating factor is e%5Eint%28sint%2Cdt%29+=+e%5E%28-cost%29.

This then implies y%2Ae%5E%28-cost%29+=+-e%5E%28-cost%29+%2B+C, or y+=+-1+%2B+Ce%5Ecost.

Plugging in y(0) = 7, and solving for C, you should get y%28t%29+=+-1+%2B+%288%2Fe%29e%5Ecost, for π < t ≤ 2π.