Solve each of the following differential equations:

1. 2xy(dy)/(dx)+(1+x)y²=e^(x)
2. cosy(dy)/(dx)+siny=x²
3. (x+1)dy-(y+1)dx=(x+1)\√(y+1)dx
4. Let v=y+1

Which of the following options correctly represents the given set of differential equations?

A) 2xy(dy)/(dx)+(1+x)y²=e^(x)
B) cosy(dy)/(dx)+siny=x²
C) (x+1)dy-(y+1)dx=(x+1)\√(y+1)dx
D) Let v=y+1