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Topin
Nov 11, 2007, 10:26 AM
Hi,
I currently have the equation:

γ*tan(α) = sin(α') / (cos(α') + β)

I was using α as the subject however in order to do my calculations I need α' to be the subject.
Does anyone know how I could rearrange this to that I have one case of α' on its own?
Thanks

terryg752
Nov 14, 2007, 09:09 AM
Let left hand side = J

Let tan a` = x

J = sin(α') / (cos(α') + β)

= tan(a`)/(1 + β sec a`)

J ((1 + β sec a`) = tan (a`)

1 +β sec a` = 1/J tan (a`)

β sec a` = 1/J tan (a`) - 1

Squaring both sides, and let tan (a`) = x

(sec^2 a` = 1 + tan^2 a`)

β^2 (1 + x^2) = [ 1/J x - 1]^2

This is a quadratic in x

Find value of x and substitute value of J

tan (a`) = x

etc.