Problems: Solve the following differential equations, 2 1) √1+x². y'-3x√y ²2-1=0. 2) 2yy' x(1-2y), y(1)=1. 3) (x²-4)y' = x(1-2y), y(√5)=1. 4) 2(1+x)(1+y).y'+(y+ 2)²=0. 5) (1+3y²).y'+2yln(1+x)=0. 6) (1+x)yyx(1+y+ y²)=0. 7) (1-xy+x2 y2)dx = (x² - x³y)dy.