Question

 а) y′ – y + 4 = 0, если y = 5 при x = 0

Answer 1

$y'-y+4=0 y(0)=5 \ y'=y-4 \ \ frac{dy}{dx}=y-4 \ \ dy=(y-4)dx \ \ frac{dy}{y-4}=dx \ \ int frac{dy}{y-4}=int dx \ \ ln|y-4|=x+C \ \ ln|5-4|=0+C \ \ ln1=0+C \ \ C=0 \ \ ln|y-4|=x$