Summation Rules

  • #1

Main Question or Discussion Point

n
∑ 3
k=0

How does this make sense when k=0?
 

Answers and Replies

  • #2
319
64
The sum is ##3+3+...=3(n+1)##
 
  • #3
The sum is ##3+3+...=3(n+1)##
Oh okay. The lower bound is the index origin and doesn't matter if it is negative?
n
∑ 3
k=-1
3+3+...=3(n+2)
 
  • #4
319
64
Correct!
 
  • #5
DrClaude
Mentor
7,155
3,295
To summarise,
$$
\sum_{k=a}^{b} c = c (b-a+1)
$$
for constant ##c##.
 
  • #6
jbriggs444
Science Advisor
Homework Helper
2019 Award
8,315
3,148
To summarise,
$$
\sum_{k=a}^{b} c = c (b-a+1)
$$
for constant ##c##.
i.e. one is counting fence posts, not sections of wire.
 

Related Threads on Summation Rules

  • Last Post
Replies
1
Views
673
  • Last Post
Replies
5
Views
639
  • Last Post
Replies
3
Views
994
  • Last Post
Replies
3
Views
2K
  • Last Post
Replies
6
Views
1K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
9
Views
2K
  • Last Post
Replies
2
Views
3K
  • Last Post
Replies
2
Views
2K
Top