Derivation of Page 1 Equations

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We define acceleration to be change in velocity during a change in time.

  a = Dv /D t
 we choose to define Dv as (v - v o) (final velocity - initial velocity)
 we choose to define Dt as t final - t initial = t - 0 = t (elapsed time)

 a = v - vo/t

 v = vo + at

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 We take it as axiomatic that distance = v avg x time
 v avg = (v final + v initial)/ 2 = (v + vo) /2
 x = (v + vo) t /2

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 Take  x = (v + vo) t /2 and substitute v = vo + at

 x = ([vo + at] + vo) t /2

 x = vo t + 1/2 a t^2

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 Take  v = vo + at and square both sides
  v^2 = vo^2 + 2 vo at + a^2t^2
 This factors to   v^2 = vo^2 + 2a [vo t + 1/2 at^2]
 substituting from table 3  x = vo t + 1/2 a t^2
  This factors to   v^2 = vo^2 + 2ax


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