GREAT ZIMBABWE UNIVERSITY . HMAT 101 GARY MAGADZIRE SCHOOL OF AGRICULTURE AND NATURAL SCIENCES DEPARTMENT OF MATHEMATICS AND COMPUTER SCIENCE ‘ RESEARCHBSc HONOURS IN MATHEMATICS EXAMINATIONS: PART 1 SEMESTER 1BSc HON EXAMINATION: ASSIGNMENT 2 HMAT 101: CALCULUS I DUE DATE: 30/09/19 Time : OF YOUR CHOICE hours Candidates may attempt ALL questions A1. Evaluate each of the following integrals: Z √ (a) x2 2x3 + 4dx, Z 1 x ln(x + 3)dx. (b) [5] [5] 0 Z (c) 3 x2 e2x dx. [5] Z 1 dx, a2 + x 2 R (e) x2 sin xdx, Z 1 − x + 2x2 − x3 (f) dx. x(x2 + 1)2 Z 1 dx p (g) , (x + 2)(3 − x) −1 Z x2 + 2x − 1 (h) dx. 2x3 + 3x2 − 2x (d) [4] [5] [6] [6] [8] page 1 of 4 HMAT 101 A2. Suppose that the amount of money in a bank account after t years is given by, t2 A(t) = 2000 − 10te5− 8 . Determine the minimum and maximum amount of money in the account during the first 10 years that it is open. [4] A3. 1 is not uniformly continuous in 0 < x < 1. x (b) Show that if y = tan−1 x, then (a) Prove that f (x) = (1 + x2 ) [4] d2 y dy = 0. + 2x 2 dx dx [4] A4. (a) Show that if f (x) and g(x) are continuous at x0 then f (x)g(x) is also continuous at x0 . [3] x+2 (b) Use the definition of a derivative to find the derivative of f (x) = . [5] x−2 (c) Let f (x) = x3 + 2x2 − x − 1. Find a number x0 ∈ (−2, 1) so that the tangent to the graph of y = f (x) is horizontal at x = x0 . [5] A5. (a) If x2 y + y 3 = 2, find d2 y , dx2 at the point (1; 1). (b) If exy − ln y = x2 + 1, find [4] d2 y . dx2 [5] (c) Prove the formula 0 0 0 (f (x)g(x)) = f (x)g(x) + g (x)f (x), assuming that g and f are differentiable. A6. [6] (a) State and prove the Mean Value Theorem. [5] 3 (b) Verify the Mean Value Theorem for f (x) = x − 12x on [−1, 3]. [4] (c) Verify the Rolle’s theorem for f (x) = x2 (1 − x)2 , 0 ≤ x ≤ 1. [4] (d) Verify the Rolle’s Theorem given that, f (x) = (x − a)m (x − b)n , where m and n are positive integers and where a < b. [6] page 2 of 4 HMAT 101 (e) Use the Mean Value Theorem or otherwise to prove that if 0 < a < b, then a b b 1− < ln < −1 . b a a [5] (f) Hence or otherwise show that 1 1 < ln(1.2) < . 6 5 [3] END OF QUESTION PAPER page 3 of 4