Freeflows
Residue System Sum Difference
For each positive integer $ n $, the set of integers $ \{0,1,\ldots,n-1\} $ is known as the $ \textit{residue system modulo} $ $ n $. Within the residue system modulo $ 2^4 $, let $ A $ be the sum of all invertible integers modulo $ 2^4 $ and let $ B $ be the sum all of non-invertible integers modulo $ 2^4 $. What is $ A-B $?
- 1
- 2
- 3
- +
- 4
- 5
- 6
- -
- 7
- 8
- 9
- $\frac{a}{b}$
- .
- 0
- =
- %
- $a^n$
- $a^{\circ}$
- $a_n$
- $\sqrt{}$
- $\sqrt[n]{}$
- $\pi$
- $\ln{}$
- $\log$
- $\theta$
- $\sin{}$
- $\cos{}$
- $\tan{}$
- $($
- $)$
- $[$
- $]$
- $\cap$
- $\cup$
- $,$
- $\infty$