# Why 2p=ln[(1-cost)/(1+cost)] => t=(1/coshp)^2

1. Jan 30, 2007

### astronomia84

why
2p=ln[(1-cost)/(1+cost)] => t=(1/coshp)^2
:surprised
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Last edited by a moderator: Jan 30, 2007
2. Jan 30, 2007

### theperthvan

why not????

3. Jan 30, 2007

### murshid_islam

i think you wrote it wrong. it should be
$$\sin^{2}t = \left(\frac{1}{\cosh p}\right)^2$$

4. Jan 30, 2007

### cristo

Staff Emeritus
What is the actual question you are asking here? Are you asking why, or if, the left implies the right. Have you done anything to attempt to show this? I doubt anyone will help unless you firstly specify your question, and secondly show some effort!