TODO:
Aplicaitons: SHM Wave eqn Superposition / beats Interference…
consider the funciton psi of x : ѱ(x) = sin(kx), where k is some constant (wavenumber)
what is the wavelength of this wave?
what is ѱ'(x) ?
what is ѱ(x) ?
what is ѱ
'(x) ?
see a pattern?
bonus: what is the 1000 th derivative ѱ(x) ?
sin(kx)+sin(kx + d) = 0 for what values of d is the above equation true?
sin(kx)+sin(kx + c) = 2sin(kx) for what values of c is the above equation true?
sin(x)+cos(x) = Asin(x+B) what are the values of A and B ?
sin(x)+cos(x) = Ccos(x+D) what are the values of C and D ?
sin(x+a) = Esin(x) + Fcos(x) What are the values of E and F (expressed in terms of a) ?
Hint: the only thing you need to know to derive all of the above is the following three formulas:
(1) sin^2 x + cos^2 x + 1 (2) sin(a+b) = sin(a)cos(b) + sin(b)cos(a) (3) cos(a+b) = cos(a)cos(b) - sin(a)sin(b)
Eqns (2) and (3) come witha little mnemonic sin –> sico sico cos –> coco - sisi (the negative sign because it is not good to be a sissy)
If you know (1), (2), (3) you kick ass !