Functions

Problem Set #1

Solutions

Problems

1. Each set of ordered pairs comes defines a mapping. Decide (yes or no) if the mapping is a function or not.

a) { (2,1), (3,4), (4,-2), (5,3), (6,3), (7,2), (8,2) } Yes. Only a single y for any x.

b) { (1,1), (3,1), (4,-2), (1,3), (7,6), (6,7), (0,2) } No 1 is mapped to both 1 and 3.

c) { (2,1), (3,1), (4,1), (5,1), (6,1), (7,1), (8,1), (9,1), (10,1) } Yes. Graph points on the horizontal line y=1

2. For each part in Problem 1 that was a function, specify its domain and range

1a) domain: {2,3,4,5,6,7,8} range: { -2,1,2,3,4}

1c) domain: {2,3,4,5,6,7,8,9,20 } range: {1}