KENDRIYA VIDYALAYA DANAPUR CANTT, (FS) SUB:- MATHEMATICS CLASS:- XII Time:- 3hrs MM:-100 General Instructions:1. All questions are compulsory 2. The question paper consists of 26 questions divided into three sections A,B & C. Section A comprises of 6 questions of 1 Marks each. Sections B comprises of 13 questions of 4 Marks each and Section C comprises of 7 questions of 6 marks each. 3. All question in section a are to be answered in one word, one sentence or as per the exact requirement of the question. 4. There is no overall choice. However internal choice has been provided in 4 questions of 4 marks each and 2 questions of 6 mark each. You have to attempt only one of the alternatives in all such questions. 5. Uses of calculator are not permitted. You may ask for logarithmic table if required. Section – A 3 1. Find the value of tan(sin-1 ) 5 1 đđĨ 2. ∫0 1+đĨ2 3. The degree of differential eqn . đ2đĻ đđĻ + 5x (đđĨ ) 2 – 6y = 10 g x is? đđĨ 2 4. Find the projection of the vector đâ = 2i + 3j +2k on the vector âđâ = ^đ+2 ^đ+ đ^ 5. Show that the vectors 2 ^đ - 3 ^đ + 4 đ^ and -4 ^đ +6 ^đ - 8 đ^ are collinear. 6. Write the vector eqn of the following line đĨ−5 3 = đĻ+4 7 = 6−đ§ 2 Section – B 7. Prove that the relation R in the set A= {1,2,3,4,5} given by R=} (a-b):|a-b| is even is an equivalence relation. OR gf f:Rī R and g: Rī R are given by f(x) = sin đĨ and g(x) = 5x 2 find gof (x) and fog (x). 8. Solve it 1−đĨ 1 tan-1 = tan−1 đĨ (x > 0) 1+đĨ 2 9. Obtain the inverse of the following matrix using elementary operations. 012 A= [1 2 3] 311 10. By using properties of determinants show that 1 x x2 x2 1 x =(1-x3 )2 x x2 1 OR a2 +1 ab ac ab b2+1 bc ca cb = 1+a2+b2+c2 c2 +1 11. Find the value of K so that the function f is continuous at the indicated point. đ˛đđđ đ đ −đđ if x ≠ đ if x = đ đ f(x) = 3 12. đ Differentiate the following function w.r.t. x. cos x. cos2x. cos3x đ at x = đ or (log x )x + x logx 13. A balloon, which always remains spherical on inflation, is being inflated by pumping in 900 cubic centimeters of gas per second. Find the rate at which the radius of the balloon increases when the radius is 15cm. 14. Integrate the following function – e2x - 1 e2x +1 or Find x2+1 x2 đ/2 -5x+b dx 15. Evaluate ∫0 16. Find the general solution of the differential equation ydx – (x+2y2) d y = 0 17. If a, b ,c are unit vectors such that log sin đĨ đđĨ a + b + c = O find the value of a. b + b . c + c . a 18. Find the shortest distance between the lines whose vector equations are and 19. ^ ^ ^ ^ ^ r = ( đ + 2 đ + 3đ^) + â ( đ - 3 đ + 2đ ) ^ ^ ^ ^ ^ ^ r = 4 + 5 + 6 +đ (2 + 3 + ) đ đ đ đ đ đ Maximise z = 3x + 4y subject to the constraints x+y≤4 x≥O y≥O SECTION – C 20. 21. A binary operation * on set R-} -1} is defined as a*b = a + b + ab ∀ a,b ∈ R-}-1}. Prove that * is commutative and associative. Also find the identity element for a ∈ R -} -1} if exists. Prove that the volume of the largest cone that can be inscribed in a sphere of radius R is 22. 23. 8 27 or Show that the semi vertical angle of the cone of the maximum volume and of given slant height is tan-1 √2. Find the area of the the region in the first quadrant enclosed by the x – ais, the Line y = x and the circle x2 = y2 = 32. or Find the area of the region bounded by the cures y= x2 + 2, y = x, x = 0 and x = 3. Show that the family of curves for which the slope of the tangent at any point (x ,y) on it is 24. of the volume of the sphere. đĨ2+đĻ2 2đĨđĻ is given by x2 – y2 = cx. Find the equation of the plane through the intersection of the planes 3x – y + 2z – 4 = 0 and x + y + z -2 = 0 and the point (2,2,1) or Find the angle between the line 25. 26. đĨ+1 2 đĻ =3= đ§−3 6 and the plane 10x + 2y – 11z = 3. A company manufactures two types of stickers A: “ SAVE EVVIRONMENT” and B: “ BE COURTEOUS” Type A requires 5 minutes each for cutting and 10 minutes each for assembling. Type B requires 8 minutes each for cutting and 8 minutes each for assembling. There are 3 hours and 20 minutes available for cutting and 4 hours available for assembling in a day. He earns a profit of Rs 50 on each type A and Rs 60 on each type B. How many stickers of each type should be company manufacture in a day to maximize profit? Give your views about “SAVE ENVIRONMENT” and “BE COURT EOUS”. There are three coins. One is a two headed coin (heaving head on both faces)another is a biased coin that comes up heads 75% of the time and third is an unbiased coin. One of the three coins is chosen at random and tossed, it shows heads, what is the probability that it was the two heads lion? -------------------------------------------------end------------------------------------------Sh. Bhola Singh PGT, (Maths) K.V Danapur Cantt (FS). Kendriay Vidyalaya Danapur Cantt, FS Mathematics Class – XII Blue print SI. NO Name of Chapter 1 Relation functions 2 Algebra 3 V. Short Q. 1 Marks Long Q. 4Marks Long Q. 6 Marks Total 1 (4) 1 (6) 2 (10) 1 (1) 3 (4) - 4 (13) Calculus 2 (1) 6 (4) 3 (6) 11(44) 4 Vectors and 3D 3 (1) 2 (4) 1 (6) 6 (17) 5 Linear programming - - 1 (6) 1 (6) 6 Probability - 1 (4) 1 (6) 2 (10) 7 Total 6 (1) 13 (4) 7 (6) 26 (100) and -