Graphing Trigonometry Equations
Date: 5/15/96 at 15:4:32 From: Anonymous Subject: Graphing Trigonometry Equations I am currently taking Mathematics 12 through correspondance, and I haven't had very much trouble so far. But recently I came upon a subject which the textbook barely covers. Here is an example that is meant to be graphed: Cos A Cos 3A - Sin A Sin 3A This is equal to Cos (A + 3A) or Cos 4A. But how do I graph this one: Sin A - Cos A Is there an identity that I am forgetting? Thanks for your help. Aaron S.
Date: 11/11/96 at 22:46:53 From: Doctor Robert Subject: Re: Graphing Trigonometry Equations I am not sure that I completely understand your question. If you are to graph y = sin x - cos x, you can make a table of values and plot the graph without resorting to any identity to simplify it. This function can be very easily graphed on a graphing calculator. If you need to have the function in terms of only one trig function, you could use the fact that cos A = sqrt(1 - sin^2 A) so that your function would be: y = sin A - sqrt(1 - sin^2 A) if that makes it any easier! -Doctor Robert, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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