Hyperbolic Functions and Tangent Line Slope 2 at y=sinhx

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Homework Help Overview

The discussion revolves around finding points on the graph of y = sinh(x) where the tangent line has a slope of 2. Participants are exploring the implications of derivatives and properties of logarithms in this context.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the derivative of sinh(x) and its relation to the slope of the tangent line. There are attempts to manipulate equations involving logarithms and exponentials to find solutions. Some participants question the validity of logarithmic properties used in the calculations.

Discussion Status

The discussion is active, with various approaches being explored. Some participants have provided guidance on transforming the equation into a quadratic form, while others are examining the implications of the logarithmic properties. There is no explicit consensus on the correct path forward.

Contextual Notes

Participants note that certain logarithmic manipulations may not be valid, and there are constraints regarding the use of inverse functions for negative values. The problem appears to be framed within the context of homework rules that may limit certain methods.

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Find the points on the graph of y=sinhx at which the tangent line has slope 2

dy/dx=coshx=2

(e^x+e^(-x))=4
x-x=ln4
 
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You have used an incorrect property of logarithms.

[tex]\log (a+b) \neq \log a + \log b[/tex].

There is no "useful" property for the log of a sum.

For solve that equation you have, try thinking about how you can make that a quadratic equation in e^x.
 
y=sinhx
y'=coshx=2
cosh^2x-sinh^2x=1
sinh^2=3
sinhx=+||-3^(1/2)=(e^x-e^(-x))/2
e^x-e^(-x)=+||-2*3^(1/2)
x=ln(+||-2*3^(1/2))/2
y=+||-e^(1/2)
 
[tex] \frac{d}{dx}sinhx=coshx=2[/tex]
[tex] cosh^2x-sinh^2x=1=4-sinh^2x[/tex]
[tex] sinhx=3^{1/2}[/tex]
[tex] sinhx=-3^{1/2}[/tex]
[tex] sinhx=\frac{e^x-e^{-x}}{2}=3^{1/2}[/tex]
[tex] e^x-e^{-x}=2*3^{1/2}[/tex]
[tex] 2x=ln2+ln(3^{1/2})[/tex]
[tex] x=\frac{ln2+ln(3^{1/2})}{2}[/tex]
using the same methods for sinhx=-3^(1/2) does not work since taking the natural log of -sqrt3 this probelms should be solvable without inverses
 

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