MULTIPLE CHOICE QUESTIONS CHAPTER – 9 DIFFERENTIAL EQUATIONS 3 d 2 y dy dy Q1. The degree of the differential equation 2 sin 1 0 is: dx dx dx (a) 3 2 (b) 2 (c) 1 (d) not defined d2y dy Q2. The order of the differential equation 2 x 3 y 0 is: 2 dx dx 2 (a) 2 (b) 1 (c) 0 (d) not defined Q3. The solution of the differential equation e x 1 y dy y 1 e x dx is: (a) e y c e x 1 y 1 Q4. The solution of the differential equation (a) e1 y x x2 c 2 (d) none of these dy 1 x y xy is: dx (b) log 1 y x Q5. The solution of the differential equation (c) y e x 1 y 1 (b) e y c e x y 1 x2 c 2 (c) e y x x2 c 2 (d) none of these dy 1 y 2 0 is: dx 1 x2 (a) y sin 1 y sin 1 x c (b) sin 1 y sin 1 x c (c) sin 1 y sin 1 x c (d) none of these Q6. The solution of the differential equation x 1 y 2 dx y 1 x 2 dy 0 is: (a) sin 1 x sin 1 y c Q7. The solution of the differential equation (a) x 2 y 2 cx (d) none of these dy y 2 x 2 is: dx 2 xy (b) x 2 y 2 cy Q8. The solution of the differential equation (a) y sin x c cos x (c) tan 1 x tan 1 y c (b) 1 x 2 1 y 2 c (c) x 2 y 2 cx (d) none of these dy y tan x sec x is: dx (b) y sin x c cos x (c) y sin x sin x c Prepared by Amit Bajaj Sir | Downloaded from http://amitbajajmaths.blogspot.com/ (d) none of these Page 1 Q9. The integrating factor of the differential equation x log x (a) log log x (b) e x dy y 2log x is: dx (c) log x Q10. The solution of the differential equation (d) x dy y sin x is: dx x (a) x y cos x sin x c (b) x y cos x sin x c (c) x y cos x cos x c Q11. The solution of the differential equation 2 x (a) circles (a) sin dy y 3 represents: dx (b) straight lines (c) ellipses Q12. The solution of the differential equation x x xc y (b) sin (d) parabolas dy y y x tan is: dx x y cx x (c) sin Q13. The solution of the differential equation x 2 y 2 (a) x2 y 2 12 x c (d) none of these (b) x2 y 2 3x c x cy y (d) sin y cy x dy 4 is: dx (d) x3 y3 12 x c `(c) x3 y3 3x c Q14. The solution of the differential equation x dx y dy x 2 y dy y 2 x dx is: (a) x 2 1 c 1 y 2 (b) x 2 1 c 1 y 2 (c) x3 1 c 1 y 3 y dy dx Q15. The solution of the differential equation x 2 1 (a) y 2 x 2 (b) y 1 x 1 x (d) x3 1 c 1 y 3 1 0 is: (c) y x x 1 Q16. The solution of the differential equation x (a) tan 1 log y c y 2 (d) y 1 x 1 x dy x 2 xy y 2 is: dx x2 x y (b) tan 1 log x c (c) tan 1 log x c x y (d) none of these ANSWERS 1. d d 2. a 3. a 16. d 4. b 5. c 6. b 7. c 8. b 9. c 10. a 11. d 12. b Prepared by Amit Bajaj Sir | Downloaded from http://amitbajajmaths.blogspot.com/ 13. d 14. a 15. Page 2