MedVision ad

exponential differentiation (1 Viewer)

C6H12O6-Glucose

New Member
Joined
Mar 23, 2009
Messages
21
Location
Canberra
Gender
Male
HSC
2008
can somebody please show me how to find y' for the following:

e<SUP>x<SUP>4</SUP>y</SUP> = x + y

ty
 

GUSSSSSSSSSSSSS

Active Member
Joined
Aug 20, 2008
Messages
1,102
Location
Turra
Gender
Male
HSC
2009
e^(y.x^4) = x + y
differentiate implicitly:

(y.4x^3 + dy/dx . x^4)e^(y.x^4) = 1 + dy/dx

re-arranging

dy/dx . (x^4 . e^(y.x^4)) - dy/dx = 1 - 4yx^3 . e^(y.x^4)
dy/dx = (1 - 4yx^3 . e^ (y.x^4)) / (x^4 . e^(y.x^4))

is that rite??? its too hard to see any simplifying on the computer screen lol xD
 

bored of sc

Active Member
Joined
Nov 10, 2007
Messages
2,314
Gender
Male
HSC
2009
can somebody please show me how to find y' for the following:

e<SUP>x<SUP>4</SUP>y</SUP> = x + y

ty
Implicit differentiation?

To find y' or dy/dx you differentiate each term separately and wherever you have differentiated y you multiply it by dy/dx.

ex4y = x + y

Differentiating:

4x3ex4y + ex4y.dy/dx = 1 + dy/dx

Now replace e<SUP>x<SUP>4</SUP>y</SUP> with x + y

4x3(x+y) + (x+y)dy/dx = 1 + dy/dx

(x+y)dy/dx -dy/dx = 1 - 4x3(x+y)
(x+y-1)dy/dx = ditto
dy/dx = [1-4x3(x+y)] / (x+y-1)
 

Drongoski

Well-Known Member
Joined
Feb 22, 2009
Messages
4,255
Gender
Male
HSC
N/A



Is my answer wrong ??

Edit

On reflection, much easier to implicitly differentiate direct without all the above hassle.
 
Last edited:

Drongoski

Well-Known Member
Joined
Feb 22, 2009
Messages
4,255
Gender
Male
HSC
N/A
e^(y.x^4) = x + y
differentiate implicitly:

(y.4x^3 + dy/dx . x^4)e^(y.x^4) = 1 + dy/dx

re-arranging

dy/dx . (x^4 . e^(y.x^4)) - dy/dx = 1 - 4yx^3 . e^(y.x^4)
dy/dx = (1 - 4yx^3 . e^ (y.x^4)) / (x^4 . e^(y.x^4))

is that rite??? its too hard to see any simplifying on the computer screen lol xD

GUS ..SSS

Don't forget: e^(y.x^4) = x+y
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top