Recent content by 707miranda

  1. 7

    Differentiation of cos(x)cos(y) or sin(x)sin(y)

    1,000 thanks I'm not worthy.
  2. 7

    Differentiation of cos(x)cos(y) or sin(x)sin(y)

    [SOLVED] differentiation of cos(x)cos(y) or sin(x)sin(y) Homework Statement Determine if the equation is exact, if exact solve. [cos(x)cos(y)+2x]dx-[sin(x)sin(y)+2y]=0 Homework Equations I have forgotten how to take the derivative of cos(x)cos(y) or sin(x)sin(y). Is this a product rule...