implicit differentiation (1 Viewer)

shaon0

...
Joined
Mar 26, 2008
Messages
2,029
Location
Guess
Gender
Male
HSC
2009
can someone please show me how to derive x/y and x^2/y^2 w.r.t x


thank you
d/dx (x/y) = (y+xy')/y^2 [By quotient rule]

d/dx (x^2/y^2)
= d/dx ((x/y)^2)
= 2(x/y).d/dx (x/y) [By chain rule]
= 2x/y.(y+xy')/y^2
= 2x(y+xy')/y^3

Might be a problem in the solution.
Just treat it as a normal derivative but when differentiating y wrt x, let d/dx (y)=dy/dx=y'
 
Last edited:

bob fossil

Member
Joined
Oct 22, 2009
Messages
225
Location
newcastle
Gender
Male
HSC
2010
d/dx (x/y) = (y+xy')/y^2 [By quotient rule]

d/dx (x^2/y^2)
= d/dx ((x/y)^2)
= 2(x/y).d/dx (x/y) [By chain rule]
= 2x/y.(y+xy')/y^2
= 2x(y+xy')/y^3

Might be a problem in the solution.
Just treat it as a normal derivative but when differentiating y wrt x, let d/dx (y)=dy/dx=y'


Thank you
 

bob fossil

Member
Joined
Oct 22, 2009
Messages
225
Location
newcastle
Gender
Male
HSC
2010
I know it's picky, but you actually "differentiate". Deriving is different.
i really need to learn the language lol i got the first letter right lol


can anyone make sence of what this question is asking?

The tangent at P(3, 3/2) on the curve 3y+xy-3x=0 cuts the y axis at T. The ordinate PG meets the x axis st G. show that:

[OG]^2=3xOT


found gradient.
found equation of tangent.
found T at 3,0
dont know how an ordinate can meet the x axis?
 

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

Top