What is Difference: Definition and 1000 Discussions

A finite difference is a mathematical expression of the form f (x + b) − f (x + a). If a finite difference is divided by b − a, one gets a difference quotient. The approximation of derivatives by finite differences plays a central role in finite difference methods for the numerical solution of differential equations, especially boundary value problems.
Certain recurrence relations can be written as difference equations by replacing iteration notation with finite differences.
Today, the term "finite difference" is often taken as synonymous with finite difference approximations of derivatives, especially in the context of numerical methods. Finite difference approximations are finite difference quotients in the terminology employed above.
Finite differences were introduced by Brook Taylor in 1715 and have also been studied as abstract self-standing mathematical objects in works by George Boole (1860), L. M. Milne-Thomson (1933), and Károly Jordan (1939). Finite differences trace their origins back to one of Jost Bürgi's algorithms (c. 1592) and work by others including Isaac Newton. The formal calculus of finite differences can be viewed as an alternative to the calculus of infinitesimals.

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  1. Jonathan1218

    Mathematical difference between permutation&combination

    I know to calculate a combination with n options and r selections while repetition is allowed you are supposed to do (n+r-1)! / r!(n-r)! and the purpose of r! as a denominator is to act as a ratio to eliminate same outcomes but of different orders and is what makes us calculate the combination...
  2. P

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  3. HCverma

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  4. J

    B When Difference between Kelvin and Celsius are negligible

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  5. J

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    So I'm kind of confused. The way I understand it, an electromagnetic field is just a regular electric field viewed from a relativistic point of view, meaning that since we see the charges moving relative to us, we feel like the particles and the fields created by them come closer together (I...
  6. HCverma

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  7. lordlarddallas

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  8. Krushnaraj Pandya

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  9. T

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  10. S

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  11. R

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  12. R

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  13. Krushnaraj Pandya

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  14. Quentin_alex

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  15. M

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  16. HCverma

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  17. F

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  18. D

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  19. S

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  20. S

    I What's the difference between Euclidean & Cartesian space?

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  21. M

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  22. M

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  23. avner yakov

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  24. Chris Lyddon

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  25. Kenneth Boon Faker

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    I've been reading about Quantum Field Theory. It strikes me that since the 1920's, physicists have changed the name "wave" to "field". I can't tell the difference between today's "fields" and what was described a "wave" in quantum theory in the early 1900's. So in quantum physics, is there a...
  26. S

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  27. Ravik Rocha

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  28. opus

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  29. J

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  30. H

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  31. C

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  32. K

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  33. M

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  34. N

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  35. M

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  36. F

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  37. A

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  38. Mr Davis 97

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  39. J

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  40. K

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  41. caters

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  42. Mr Davis 97

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  43. C

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  44. T

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  45. Simonel

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  46. P

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  47. A

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  48. axer

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  49. Ranku

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  50. S

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