Section 1.2 Extra Practice STUDENT BOOK PAGES 10–21 1. Calculate the slope of the line through each pair of points. a. (6, ⫺2), (3, 4) 7 4 b. a , 1b , a⫺5, b 5 6 c. (4.3, 0.7), (2, 6.1) 2. State the equation and sketch the graph of the following lines: a. having slope 4 and y-intercept ⫺2 b. passing through (2, 1) and (3, 6) c. having x-intercept ⫺3 and y-intercept 7 3. Simplify the following difference quotients. (1 ⫹ h) 2 ⫺ 1 a. h (9 ⫹ h) 2 ⫺ 81 b. h 5 5 x ⫹ 2 ⫺ 2 c. x 4. Rationalize each of the following numerators to obtain an equivalent expression. 兹h ⫹ 49 ⫺ 7 h 兹x ⫹ 2 ⫺ 兹2 b. x Copyright © 2009 by Nelson Education Ltd. a. 5. Determine the slope of the tangent to each curve at the given point. a. y ⫽ 2x 2; (⫺2, 8) b. y ⫽ ⫺10x ⫹ 3; (6, ⫺57) 1 1 c. y ⫽ ; a4, b x 4 6. For the equations in question 5, use a graphing calculator to approximate the slope. 7. Consider several different linear functions (lines of the form y ⫽ mx ⫹ b). By finding tangent lines at a point and using graphing technology, determine what the slope is at every point of a linear function. 8. Determine the slope of the tangent to each curve at the point which is given below. a. y ⫽ 兹x ⫹ 4 at (5, 3) b. y ⫽ 兹x ⫺ 1 at (26, 5) c. y ⫽ 兹2x ⫺ 3 at (2, 1) 9. Determine the slope of the tangent to each curve at the point which is given below. 3 a. y ⫽ ; x ⫽ ⫺4 x 5 b. y ⫽ ;x⫽1 2⫹x 10 c. y ⫽ ⫺ ; x ⫽ ⫺5 10 ⫹ x 10. Determine the slope of the tangent to each curve at the point whose x-value is given. a. f (x) ⫽ x 2 ⫺ 4x; x ⫽ 1 20 1 b. f (x) ⫽ ;x⫽ x 2 c. f (x) ⫽ 2x 2; x ⫽ ⫺1 d. f (x) ⫽ 兹x ⫺ 11; x ⫽ 15 11. Show that, at the point of intersection of the cubic functions f (x) ⫽ x 3 and g (x) ⫽ 14 ⫺ x 3, the slopes of the tangents to each function are negatives of each other. Section 1.2 Extra Practice 325