How do we show that 2.2.19 and 2.3.21 are equal in this textbook?

Join the discussion
Registration is free. Start your own thread to ask a follow-up.
Sign up Log in
1 reply · 3K views
Physics news on Phys.org

Discussion

hi crocomut! :smile:

standard trick:

swap i and j … since they're both dummy indices, that gives you the same expression!

then add, and divide by 2 :wink:​
 

Similar threads

Graduate How do we show that the interior of a Faraday cage is an equipotential?
  • etotheipi
  • · Replies 10 ·
  • Electromagnetism
Replies
10
How do we show that it is finite?
  • evinda
  • · Replies 4 ·
  • Differential Equations
Replies
4
Why do we show in this way that it is not the image of the function?
  • evinda
  • · Replies 1 ·
  • Set Theory, Logic, Probability, Statistics
Replies
1
Graduate How can we show that the annihilation operators satisfy the given equation?
  • etotheipi
  • · Replies 10 ·
  • Quantum Physics
Replies
10
How do we show that $L$ is diagonalizable?
  • Chris L T521
  • · Replies 1 ·
  • Math Problem of the Week
Replies
1
How shall we show that this limit exists?
  • Mike400
  • · Replies 2 ·
  • Calculus and Beyond Homework Help
Replies
2
How can we show that one of these congruences hold?
  • mathmari
  • · Replies 5 ·
  • Set Theory, Logic, Probability, Statistics
Replies
5
How can we show that a continuous function satisfies a specific inequality?
  • Ackbach
  • · Replies 1 ·
  • Math Problem of the Week
Replies
1
How could we show that D is bounded and closed?
  • mathmari
  • · Replies 4 ·
  • Topology and Analysis
Replies
4
Undergrad How can we show that $D_n(t)$ has a bounded integral over a certain interval?
  • Euge
  • · Replies 2 ·
  • Math Problem of the Week
Replies
2