For the Bernoulli equation y′+y=xy2y' + y = x y^2y′+y=xy2, which linear equation results from v=y−1v = y^{-1}v=y−1?
v′−v=−xv' - v = -xv′−v=−x
v′+v=xv' + v = xv′+v=x
v′−v=xv' - v = xv′−v=x
v′+v=−xv' + v = -xv′+v=−x