Write the given hyperbolic function as simply as possible

Click For Summary
SUMMARY

The hyperbolic function expression ##\dfrac{e^x}{1+e^{2x}}## simplifies to ##\dfrac{1}{2\cosh x}## through division of the numerator and denominator by ##e^x##. This transformation eliminates the need to express 1 as ##\cosh x + \sinh x##, which is unnecessary and incorrect. The discussion emphasizes the importance of clarity in mathematical expressions and the correct application of hyperbolic identities.

PREREQUISITES
  • Understanding of hyperbolic functions, specifically ##\cosh x## and ##\sinh x##.
  • Familiarity with exponential functions and their properties.
  • Basic algebraic manipulation skills, including simplifying fractions.
  • Knowledge of mathematical notation and expressions.
NEXT STEPS
  • Study the properties of hyperbolic functions in detail.
  • Learn about the derivation and applications of hyperbolic identities.
  • Explore advanced algebraic techniques for simplifying expressions.
  • Investigate the relationship between exponential functions and hyperbolic functions.
USEFUL FOR

Students studying calculus, mathematicians, and anyone interested in simplifying hyperbolic expressions or enhancing their algebraic manipulation skills.

chwala
Gold Member
Messages
2,828
Reaction score
420
Homework Statement
##\dfrac{e^x}{1+e^{2x}}##
Relevant Equations
hyperbolic equations
My take;

##2\cosh x = e^x +e^{-x}##

I noted that i could multiply both sides by ##e^x## i.e

##e^x⋅2\cosh x = e^x(e^x +e^{-x})##

##e^x⋅2\cosh x = e^{2x}+1##

thus,

##\dfrac{e^x}{1+e^{2x}}=\dfrac{\cosh x + \sinh x}{e^x⋅2\cosh x}##

##= \dfrac{\cosh x + \sinh x}{(\cosh x + \sinh x)⋅2\cosh x}##

##=\dfrac{1}{2\cosh x}##
any other approach is welcome.
 
Last edited by a moderator:
Physics news on Phys.org
chwala said:
Homework Statement:: ##\dfrac{e^x}{1+e^{2x}}##
Relevant Equations:: hyperbolic equations

both sides
There are no 'sides'
There is no 'equation'

You post an expression. If you divide numerator and denominator by ##e^x## you see that you can rewrite the expression as ##1\over 2\cosh x##: the numerator is now ##1## and the denominator is now ##2\cosh x##. There is no need to write ##1## as ##\cosh x + \sinh x##

Cheers !

##\ ##
 
BvU said:
There are no 'sides'
There is no 'equation'

You post an expression. If you divide numerator and denominator by ##e^x## you see that you can rewrite the expression as ##1\over 2\cosh x##: the numerator is now ##1## and the denominator is now ##2\cosh x##. There is no need to write ##1## as ##\cosh x + \sinh x##

Cheers !

##\ ##
...seen that...correct man ! it's an expression ...i just posted exactly as it appears on textbook...i should have checked that or rather introduced ##f(x)## on the lhs.
 
BvU said:
There is no need to write ##1## as ##\cosh x + \sinh x##
the more so because it is totally incorrect :biggrin: ! My bad, I should have written "##e^x## as ##\cosh x + \sinh x## "
 
  • Like
Likes   Reactions: chwala

Similar threads

  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 18 ·
Replies
18
Views
3K
Replies
2
Views
1K
  • · Replies 6 ·
Replies
6
Views
1K
Replies
32
Views
3K
  • · Replies 7 ·
Replies
7
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K