(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Prove Sech^2(x) = 1 - tanh^2(x)

2. Relevant equations

TanH(x) = (e^x - e^-x)/(e^x+e^-x)

CosH(x) = (e^x+e^-x)/2

SinH(x) = (e^x - e^-x)/2

3. The attempt at a solution

SecH^2(x) = 1/cosh^2(x)

=1 / (e^x - e^-x)^2 / 4

=4/(e^x - e^-x)^2

This is where I am stuck. Any help is greatly appreciated. Thank you !

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Sech^2(x) = 1 - tanh^2(x) proof - need help!

**Physics Forums | Science Articles, Homework Help, Discussion**