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FP3 - Hyperbolic Functions

Given that artanhx - artanh y = ln5, find y in terms of x

I have no idea where to start, i turned artanh x and y into 1/2n(1+x/1-x) for both of them but i cant work out to go after there, can anyone help?
Original post by Jowen07
Given that artanhx - artanh y = ln5, find y in terms of x

I have no idea where to start, i turned artanh x and y into 1/2n(1+x/1-x) for both of them but i cant work out to go after there, can anyone help?


What do you know about the addition and subtraction of logarithms?
Reply 2
I then get to 1+x/1-x = 10+10y/1-y, cant go further
Reply 3
for the x term, for example, use the logarithmic version of arctanh(x), i.e:

arctanh(x)=12ln(1+x1x)\displaystyle arctanh(x)= \frac{1}{2} ln (\frac{1+x}{1-x})

do the same with the y term, combine the terms using the laws of logs, exponentiate, and use some algebraic manipulation.
Original post by Jowen07
I then get to 1+x/1-x = 10+10y/1-y, cant go further


multiply both sides by (1-x)(1-y) and collect like terms.

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