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

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

Let t = e ^ x > 0
Then y = (t-1 / T) / 2
t²-2yt-1=0
The positive value of solution t = y + √ (Y & # 178; + 1)
So x = ln [y + √ (Y & # 178; + 1)]
The inverse function is y = ln [x + √ (X & # 178; + 1)]