12N / 238 CLASS: B.Sc. PHYSICS St. JOSEPH’S COLLEGE (AUTONOMOUS) TIRUCHIRAPPALLI – 620 002 SEMESTER EXAMINATIONS – NOVEMBER 2012 TIME: 3 Hrs. MAXIMUM MARKS: 100 SEM SET PAPER CODE TITLE OF THE PAPER I 2012 12UPH130401 MATHEMATICS – I SECTION – A Answer all the questions: 20 x 1 = 20 Choose the correct answer: 1. The nth derivative of sin(ax+b) is a) n b) a n sin( ax b ) n a sin ax b 2 c) n d) a n cos( ax b ) n a cos ax b 2 2. a If f(x) is an odd function of x, then f ( x )dx a a) 0 b) a f ( x )dx 0 c) a 2 f ( x )dx d) 1 0 3. Differential equation is one which involves a) constant b) derivative c) variable d) zero 4. A diagonal matrix in which all the diagonal elements are equal is called a) scalar matrix b) unit matrix c) identity matrix d) none 5. The series a + ar + ar2 + … is convergence if a) |r| < 1 b) r > 1 c) r 1 d) r 1 Fill in the blanks: 6. sin nx dx = _______. 7. The nth derivative of (ax + b)m is _______. 8. dy Py Q is _______. dx The determinant of singular matrix is _______. The integrating factor of 9. 10. If an tends to a finite limit ‘a’ as n, the series an is said to be _______. State True or False: 11. The points at which f(x) is either maximum or minimum are called extreme points. b 12. b f ( x )dx f ( a x )dx a 13. a 1 d (tan x ) x dy y dx 2 x y 2 14. A symmetric matrix remains unchanged if rows and columns are interchanged. 15. The convergence or divergence of an infinite series is not affected when each of its term is multiplied by a finite quantity. Answer in one or two sentences: 16. State Leibnitz theorem. 2 4 2 17. Find sin x cos x dx 0 18. Find the complementary function of (D2 + 5D + 6) y = ex. 1 2 1 1 ; B Find AB. 19. If A 3 4 2 1 20. Define series. SECTION – B Answer all the questions: 5 x 4 = 20 21. a. If y = x2 eax then find yn. OR b. Evaluate x e x dx 22. a. Find reduction formula for I tann x dx . n OR 32 2 b. (sin x ) Evaluate dx 32 32 (cos x ) 0 (sin x ) 12 23. a. dy 1 y 2 0 Solve dx 1 x 2 OR 2 x b. Solve (D + 5D + 6) y =e 24. a. 1 1 1 1 Find the rank of the matrix A 4 1 0 2 . 0 3 4 2 OR b. 1 1 3 Find the eigen value of the matrix A 1 5 1 . 3 1 1 25. a. Determine the nature of the series 1 1 1 un 1 2 ... n 1 ... 3 3 3 OR b. n! 2n n 1 nn Discuss the convergence of the series SECTION – C Answer any FOUR questions: 4 x 15 = 60 26. Find the maximum and minimum value of the function 2x3 – 3x2 – 36x + 10. 27. Establish reduction formula for I sin n x dx and find n 2 n sin x dx 0 28. Show that the solution of the differential equation dy d2y 0 when t=0 which is such that y = 0 and 4 y A sin pt 2 dx dt 1 A sin pt p sin 2t 2 if p2. If p=2, show that is y 2 4 p A(sin 2t 2t cos 2t ) y . 8 29. Verify Cayley-Hamilton theorem for the matrix 2 1 1 A 1 2 1 and find A-1. 1 1 2 30. Prove that the series 1 k 1 1 2 k ... 1 n and divergent if k1. ************** k ... is convergent if k>1