I need to show that two equations equal one another. It's too complicated to display fully on here but I'm stuck on a step:
dF/dr = df/dx cos2(h) + df/dy sin(h)
(dF/dr)^2 = (df/dx)^2 cos^2(h) + (df/dy)^2 sin^2(h)
Does anybody know how to get rid of the cos squared and sin squared?
P.S. By (dF/dr)^2 I mean the first derivative squared not the second derivative
dF/dr = df/dx cos2(h) + df/dy sin(h)
(dF/dr)^2 = (df/dx)^2 cos^2(h) + (df/dy)^2 sin^2(h)
Does anybody know how to get rid of the cos squared and sin squared?
P.S. By (dF/dr)^2 I mean the first derivative squared not the second derivative