posted by Marrion on .
Given that a^2+b^2=2 and that (a/b)= tan(45degee+x), find a and b in terms of sinx and cosx.
I don't know what i'm supposed to do, and i don't come to an answer! Help, thanks!
a/b = (1+tanx)/(1-tanx)
i square both sides...
a^2(1-tanx)^2 = b^2(1+tanx)^2
a^2 + b^2 = 2
a^2 = 2 - b^2
(2-b^2)(1-tanx)^2 = b^2(1+tanx)^2
I don't know if im on the right track, but i don't seem to come to an answer when i expand the whole equation!
multiply both sides by cos(x) to get
Now square and simplify. The product terms will cancel out after you substitute b²=(2-a²) to give you a in terms of sin(x) and cos(x).
You can do similarly for b.