Solve the differential equation `sinxdy/dx+3y=cosx`

Explanation

`dy/dx+(3y)/sinx=cosx/sinx`

`P(x)=3/sinx`

`Q(x)=cotx`

`IF=e^(intp(x)dx)=e^(3/sinx) dx=e^(3intcosecx
)`dx

`=e^(ln(1+cosecx+cotx)^(-3)`

`y*IF=intIF*Q(x) dx`

`=int-dt/t^3`

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