An integrating factorfor the differential equation (2y² +32) dz+ 2ry dy = 0, 18 A. y-¹, B. V C. 2-¹, D. I. E. None of these. 2. 2 points The general solution to the differential equation (2x + 4y + 1) dx +(4x-3y2) dy = 0 is A. x² + 4zy+z+y³ = C. B. x² + 4xy-z-y²=C. C. 2² +4zy-z+y³ = C₁ D. z² + 4zy+z-y³ = C, E. None of these 3. 2 points The general solution to the differential equation dy 6x³-2x+1 dz cos y + ev A. siny+e=2-²-1 + C. B. sin y +e=1-1² +2+C. C. siny-ez-z²+z+ C. siny+e=2+z²+z+C. E. None of these. D.