\
The function is .
Above equation satisfies the differential equation .
Find first and second derivatives of the function and substitute those results in above differential equation to find A and B.
\.
Differentiate on each side with respect to .
Derivative of the sine function: .
Derivative of the cosine function: .
Differentiate on each side with respect to .
Substitute the values of and
in differential equation
.
\
Compare and
coefficients respectively.
Solve above two equations to find and
values.
From equation , we have
.
Substitute in
.
Substitute in
.
.
Thus, and
.
and
.