- #1
myusernameis
- 56
- 0
Homework Statement
Find a second-order initial-value problem whose solution is sin at
The Attempt at a Solution
so i know that
y' = a cos at
y" = -a^2 sin at
but the solution says that
"Then y(t) = sin at is
a solution to 2 y ''+ a y = 0 . Our initial conditions must be y(0) = 0, y '(0) = a ."
how do i know that it's 2y'' + a y? how come it couldn't be something else like y''+y'+ y?
thanks