Solution for Section 3.5 Question 5
5. Suppose that n is an odd integer. We need to show
that
n / 2
=
n / 2
+ 1.
Proof Since n is an odd integer, n = 2k + 1
for some integer k.
| Left-hand side: |
n / 2 = (2k
+ 1) / 2 = k + 1/2 = k + 1 (by the definition of
ceiling, see illustration below). |
| Right-hand side: |
n / 2 + 1 = (2k + 1) / 2 + 1 = k + 1/2 + 1 = k + 1 (by the definition of floor, see
illustration below). |

Thus
n
/ 2
=
n / 2
+ 1.
Back to Section 3.5