Express the Tangent of A in terms of the Cosine of A.
Use the trigonometric identities to convert between trigonometric functions.
Tangent A =
Tangent A = ----------
but since sine A = Square root of (1 - Cosine2 A), which can also be written as (1 - Cosine2 A)1/2 we get
(1 - Cosine2 A)1/2
Tangent A = ----------------
This can be useful if for some reason you have a cosine table but do not have a tangent table. You can then determine the value of the tangent even without the tangent table.
The trigonometric identities used above are as follows:
Tangent A = (Sine A)/(Cosine A)=----------
Sine2 + Cosine2 = 1