Solving Fresnel Coefficient Equations

[Dassinia]

Hello,
1. Homework Statement [/b]

http://imageshack.com/a/img17/2531/gu44.png Uploaded with ImageShack.com
I'm trying to prove this but i didn't succeed

Homework Equations

The Attempt at a Solution

For the t I multiplied by sin(θt) in the numerator and denominator and used
sin(a) * cos(b) = 1/2 × (sin(a+b) + sin(a-b))
I ended with a 4cos(θt)sin(θi)/[sin(θi+θt)+sin(θt-θi)] but then ?
For r I don't even know how to start

Thanks

 

[ehild]

Hello,
1. Homework Statement [/b]

http://imageshack.com/a/img17/2531/gu44.png Uploaded with ImageShack.com
I'm trying to prove this but i didn't succeed

Homework Equations

The Attempt at a Solution

For the t I multiplied by sin(θt) in the numerator and denominator

ehild


That is all right, but use Snell's Law n_isin(θi)=n_tsin(θt) after, and see if you can simplify...

ehild

 

[Dassinia]

and for r, how can I start

 

[ehild]

The same way.

ehild