adv functions

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Show that tanx= (sinx/ cosx)
can be written as:
tan(x-y) = (tanx - tany) / (1+ tanxtany)

  • adv functions -

    write tan (x-y)
    = sin(x-y)/cos(x-y)
    = [sinxcosy - cosxsiny[/[cosxcosy + sinxsiny]

    Now divide everybody by cosxcosy and it will all fall into place.

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