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Prove: (tan y + Cot y) sin y cos y = 1

  1. Jul 25, 2005 #1
    Hi, I need to prove:

    (tan y + Cot y) sin y cos y = 1

    I've gotten this far and got stuck:

    (tany + cos y) sin y cos y changed Cot to reciprical
    --------sin y

    (sin y tany + cosy) sin y cos y common demonator

    (sin y tany + cos y) cosy multipyied by sin y

    then i could distribute

    cos y sin y tan y + cos(sqared) y but how would that equal 1?

    thanks for your time.
    Last edited: Jul 25, 2005
  2. jcsd
  3. Jul 25, 2005 #2
    It should help if you plug in

    [tex]\tan x = \frac{\sin x}{\cos x}[/itex]
    Last edited: Jul 25, 2005
  4. Jul 25, 2005 #3
    just a suggestion of my own, but try expressing those ratios literally in terms of fractions (ie: sin theta = o/h)...simplify the equation now and see if you notice anything familiar.
  5. Jul 25, 2005 #4
    o got it thank you!
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