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Fall 2014 – MATH 151, Sections 549-551 Quiz #2 DIRECTIONS. Read each problem carefully and work it out in the space provided. Put a box around the answer you believe best answers the question. Calculators are not allowed. Problem 1. Find the cosine of the angle between the two vectors h2, 5i and h−1, 3i. (a) √17 29 √ (b) (c) 3 2 √13 290 (d) None of the above. Problem 2. Let m = h1, 2i and n = h4, 3i. Find the vector projection of m onto n. (a) h 85 , 65 i (b) h8, 6i 40 √ (c) h √ , 305 i 5 (d) None of the above. 1 Math 151 Fall 2014 Quiz #2 2 Problem 3. Which of the following is a Cartesian equation of the parametric curve determined by the equations x(t) = cos2 (t), y(t) = sin(t), 0 ≤ t ≤ 2π. (a) x2 + y 2 = 1 (b) xy = 1 (c) x2 + y = 1 (d) x + y 2 = 1. Problem 4. A horizontal force of 12 lbs is acting on a box as it is pushed up a ramp that is 10 ft long and inclined at an angle of 30◦ above the horizontal. Find the work done on the box. (a) 60 ft. lbs. √ (b) 60 3 ft. lbs. √ (c) 12 2 ft. lbs. (d) None of the above.