Help needed in Mathematica
- To: mathgroup at yoda.physics.unc.edu
- Subject: Help needed in Mathematica
- From: Steve Xing Gu <sgu at henry.eecs.berkeley.edu>
- Date: Thu, 23 Jun 1994 22:43:23 -0700
I recently encountered a problem which I cannot solve sucessfully by Mathematica functions. I have a transcedental function in the form(A) of C1 Cos[X] + C2 Sin[X], and I want to use one function to convert form(A) to the form(B), C3 Cos[X + Y]. Converting from form(B) to form(A) can be easily done by the function, "TrigReduce" in "Algebra`Trigonometry`", as the example shown below: *************************************************************************** In[84]:= N[Expand[TrigReduce[5.64 Cos[t + 3 Pi / 4]]]] Out[84]= -3.98808 Cos[t] - 3.98808 Sin[t] *************************************************************************** But I've been unsucessfuly in converting from -4 Cos[t] - 4 Sin[t] to 5.64 Cos[t + 3 Pi / 4]. Handling transcedental functions is one of the weak parts of Mathematica. I appreciate any assistance on this problem. Steve Gu sgu at ohm.eecs.berkeley.edu