| ▼ | 1 | Chapter 1 |
| 1.1 | Exercise 1.1 |
| 1.2 | Exercise 1.2 |
| 1.3 | Exercise 1.3 |
| 1.4 | Exercise 1.4 |
| 1.5 | Exercise 1.5 |
| 1.6 | Exercise 1.6 |
| 1.7 | Exercise 1.7 |
| 1.8 | Exercise 1.8 |
| 1.9 | Exercise 1.9 |
| 1.10 | Exercise 1.10 |
| 1.11 | Exercise 1.11 |
| 1.12 | Exercise 1.12 |
| 1.13 | Exercise 1.13 |
| 1.14 | Exercise 1.14 |
| 1.15 | Exercise 1.15 |
| 1.16 | Exercise 1.16 |
| 1.17 | Exercise 1.17 |
| 1.18 | Exercise 1.18 |
| 1.19 | Exercise 1.19 |
| 1.20 | Exercise 1.20 |
| 1.21 | Exercise 1.21 |
| 1.22 | Exercise 1.22 |
| 1.23 | Exercise 1.23 |
| 1.24 | Exercise 1.24 |
| 1.25 | Exercise 1.25 |
| 1.26 | Exercise 1.26 |
| 1.27 | Exercise 1.27 |
| 1.28 | Exercise 1.28 |
| 1.29 | Exercise 1.29 |
| 1.30 | Exercise 1.30 |
| 1.31 | Exercise 1.31 |
| 1.32 | Exercise 1.32 |
| 1.33 | Exercise 1.33 |
| 1.34 | Exercise 1.34 |
| 1.35 | Exercise 1.35 |
| 1.36 | Exercise 1.36 |
| 1.37 | Exercise 1.37 |
| 1.38 | Exercise 1.38 |
| 1.39 | Exercise 1.39 |
| 1.40 | Exercise 1.40 |
| 1.41 | Exercise 1.41 |
| 1.42 | Exercise 1.42 |
| 1.43 | Exercise 1.43 |
| 1.44 | Exercise 1.44 |
| 1.45 | Exercise 1.45 |
| 1.46 | Exercise 1.46 |
This procedure adds the absolute value of b to a. To do this, it selects the operation to apply on a with b based on whether b is greater than 0. If b > 0, then b = abs(b) and can be added to a. Otherwise, -b = abs(b) and so a - b = a + abs(b). Note that -b = abs(b) for the case where b = 0.
(define (a-plus-abs-b a b) ((if (> b 0) + -) a b))