My Math Forum  

Go Back   My Math Forum > High School Math Forum > Algebra

Algebra Pre-Algebra and Basic Algebra Math Forum

LinkBack Thread Tools Display Modes
March 5th, 2014, 06:33 PM   #1
Joined: Mar 2014

Posts: 1
Thanks: 0

Hyperbolic function question (simple)

Hi there,

The question asks me to write the following as algebraic expressions of x.

sinh(loge x)

Now I've gotten it to the stage of:

But I can't seem to get it further without thinking that I've mucked something up. Wolfram Alpha ( ... 9+simplify) says that I can turn:

x-1/x = (x-1)(x+1)/x

That would make the answer right but am I missing some sort of rule or something? I don't know how the above line can work?

The answer is

Could somebody please explain that jump from x-1/x to (x-1)(x+1)/x for me please? Thank you.
TomQLD is offline  
March 5th, 2014, 09:44 PM   #2
Global Moderator
Joined: Dec 2006

Posts: 21,036
Thanks: 2274

(x - 1)(x + 1) = x(x + 1) - 1(x + 1) = x + x - x - 1 = x - 1, so (x-1)(x+1)/x = (x - 1)/x = x - 1/x.

I take it you're aware that sinh(x) is defined as and so sinh(ln(x)) = (x - 1/x)/2.
skipjack is offline  

  My Math Forum > High School Math Forum > Algebra

function, hyperbolic, question, simple

Search tags for this page
Click on a term to search for related topics.
Thread Tools
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
deriving hyperbolic function bongantedd Algebra 2 February 26th, 2014 03:49 PM
Inverse hyperbolic secant function Tooperoo Calculus 1 November 27th, 2013 04:27 AM
Hyperbolic cosine function unwisetome3 Trigonometry 3 September 28th, 2012 11:59 AM
Hyperbolic Function:Derivative layd33foxx Calculus 3 January 27th, 2012 02:50 PM
Hyperbolic function help Guzak Algebra 1 April 21st, 2009 10:47 PM

Copyright © 2019 My Math Forum. All rights reserved.