Summary: Math 151
Spring 2000
Common Exam 1
Key to Version A
1. Consider the line whose vector equation is r (t) = (2 - 3t) i+(-1 - t) j
Which vector is parallel to this line?
(a) 2, -1 (b) -3, -1 (c) j (d) (-1 - t) j (e) i
The easiest way to do this problem is to rewrite the expression for
r (t).
r (t) = (2, -1) + t (-3, -1)
Thus, (-3, -1) is parallel to the line.
2. Find a unit vector which points in the same direction as -1, 5 .
(a) 1, -5 (b) -1, 5 (c)
-1, 5
26
(d)
-1, 5

26
(e)

Source: Aguiar, Marcelo - Department of Mathematics, Texas A&M University

Collections: Mathematics