The University of British Columbia Science One Mathematics Midterm #1 27 October 2009 Time: 50 minutes Full Name: Student # : Signature: This Examination paper consists of 6 pages (including this one). Make sure you have all 6. Instructions: No memory aids allowed. No calculators allowed. No communication devices allowed. Rules: – Each candidate must be prepared to produce, upon request, a UBC card for identification. – Candidates are not permitted to ask questions of the invigilators, except in cases of supposed errors or ambiguities in examination questions. – No candidate shall be permitted to enter the examination room after the expiration of one-half hour from the scheduled starting time, or to leave during the first half hour of the examination. – Candidates suspected of any of the following, or similar, dishonest practices shall be immediately dismissed from the examination and shall be liable to disciplinary action: - having at the place of writing any books, papers or memoranda, calculators, computers, sound or image players/recorders/transmitters (including telephones), or other memory aid devices, other than those authorized by the examiners; - speaking or communicating with other candidates; and - purposely exposing written papers to the view of other candidates or imaging devices. The plea of accident or forgetfulness shall not be received. – Candidates must not destroy or mutilate any examination material; must hand in all examination papers; and must not take any examination material from the examination room without permission of the invigilator. – Candidates must follow any additional examination rules or directions communicated by the instructor or invigilator. marking: Q1 / Q3 / Q2 / Q4 / Names of Instructors: Eric, Fok, Mark TOTAL / Science One Mathematics — Midterm #1 — 27 October 2009 — p. 2 of 6 Q1 [5 marks] Let (a, a2 ) be any point on the parabola y = x2 . (a) Find the equation of the line, l1 , going through the point (a, a2 ) and perpendicular to the tangent line to this parabola at (a, a2 ). (b) Consider the horizontal line l2 given by y = a2 . Show that the distance between the y-intercepts of l1 and l2 is equal to 1/2 for any non-zero value of a. Science One Mathematics — Midterm #1 — 27 October 2009 — p. 3 of 6 Q2 [5 marks] (a) Define what it means for a function f to be continuous at a point c. ( q (b) Let f (x) = |x| x2 if x < c, if x ≥ c. For what value(s) of the constant c is f continuous everywhere? Science One Mathematics — Midterm #1 — 27 October 2009 — p. 4 of 6 Q3 [10 marks] Let f (x) = 1 . 1 + x2 (a) Identify intervals on which f is increasing, decreasing, concave up and concave down; and identify any minima, maxima and inflection points of f . Science One Mathematics — Midterm #1 — 27 October 2009 — p. 5 of 6 (b) Sketch f . Note: each axis must be labeled and must have at least one point indicated to provide a scale. (c) For which values of c is the function g(x) = f (x) + cx increasing everywhere on the real line? Science One Mathematics — Midterm #1 — 27 October 2009 — p. 6 of 6 Q4 [10 marks] Consider the function f (x) = x2 − 3x + 2 . x2 (4 − x) Prove, using the Intermediate Value Theorem, that f (x) takes on the value 1 at least twice.