MATH 2203 –Exam 1 (Version 2) Solutions
February 4, 2011
S. F. Ellermeyer Name
Instructions. Your work on this exam will be graded according to two criteria: mathe-
matical correctness and clarity of presentation. In other words, you must know what
you are doing (mathematically) and you must also express yourself clearly. In particular,
write answers to questions using correct notation and using complete sentences where
appropriate. Also, you must supply su¢ cient detail in your solutions (relevant calculations,
written explanations of why you are doing these calculations, etc.). It is not su¢ cient to just
write down an “answer” with no explanation of how you arrived at that answer. As a rule
of thumb, the harder that I have to work to interpret what you are trying to say, the less
credit you will get. You may use your calculator but you may not use any books or notes.
1. In R3, the set of points described by the pair of equations
x= 1
y= 0
is (circle the correct choice):
(a) a pair of planes.
(b) a plane.
(c) a pair of lines.
(d) a line.
(e) none of the above.
2. Two vectors, aand b, are pictured below.
a
b
(a) Which of the vectors pictured below is a+b? (Circle the correct choice.)
W X Y Z
(b) Which of the vectors pictured below is 2a+b? (Circle the correct choice.)
W X Y Z
(c) Which of the vectors pictured below is ab? (Circle the correct choice.)
W X Y Z
1
