Friday, February 5 Announcements WeBWorK #5 is now open Due Wednesday, February 10 at 9pm Covers material from “Week 5”—see syllabus online Quiz #2 solutions online; papers in Math Learning Centre Quiz grades: Our section’s average 4.7/10. An improvement, but still lower than we want! Essential to master: FTC1 problems with Chain Rule (like #1), and substitutions in definite integrals (like #2). Term marks scaled, so if we do well on the final, scores will come up. Just make sure we know our stuff! If you think yours wasn’t graded right: check online marking scheme first. Then hand me official “regrade form” (quizzes web page) with your quiz paper, by next Friday. Friday, February 5 Clicker Questions Clicker Question 1 Some quadratic polynomials can be factored into two linear polynomials with real numbers as coefficients: A. when c ≥ 0 B. when b2 − 4ac ≥ 0 C. when 2ax + b ≥ 0 D. always 3x2 + 7x − 6 = (x + 3)(3x − 2) √ √ x2 − 5 = (x + 5)(x − 5) E. when two of the numbers a, b, c have different signs In general: The reason: When does the quadratic polynomial ax2 + bx + c factor into two linear polynomials in this way? ax2 + bx + c factors this way ⇐⇒ it √has one or two roots ⇐⇒ b2 − 4ac is defined (by the quadratic formula)