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Expert: Alon Mandes - 11/8/2008


Question
Can you help me derive (y-2x)/(2y-x)
I know the answer is -6/(2y-x)^3
help?

Answer
to derive {(y-2x)/(2y-x)} we must keep in mind that :
d/dx {x} =1
d/dx {y} =y'
d/dx {f/g} = [(df/dx)*g-(dg/dx)*f]/g^2
So, d/dx {(y-2x)/(2y-x)}= [(y'-2)(2y-x)-(y-2x)(2y'-1)]/(2y-x)^2
Now let's open brackets:
=(2yy'-y'x-xy-4y+2x-2yy'+y+4xy'-2x)/(2y-x)^2
=(-xy-3y-3xy')/(2y-x)^2.

So, whether there is something missing in your question or the
book's answer is wrong.

Alon.  

Calculus

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Alon Mandes

Expertise

Kind of questions I can answer : Limits, Derivatives, Integration, Implicit functions, continuousity, differentiation ,Extremum problems, Lagrange multipliers, Gradients, Surface integrals, Multi variables functions ,Multi variables Integrals,Complex variables ,Complex functions, Curves, Trajectory integrals & Vector analyse,Divergence,Rotor & word problems. Kind of question I can't answer : Economics,Combinatorics,infinite series & convergence ,Statistics & Probabilities .

Experience

1. I'm a team member of mathnerds (math site for answering questions) 2. I'm a team member in the Student's Union of the Technion, helping students who have problems in mathematics. 3. 2 years of experience as a math teacher in college. 4. I give free homework help for high school students in Mathematics & Physics. 5. I teach part time in collage the subjects : "Digital Signal Processing" , "Random Signals & Noise" , "Complex Functions".

Organizations
Hi-Tech company : GSM4VOIP ; job possition : Algorythm developer.

Education/Credentials
M.A in Mathematics & Bs.c in Electronics.

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