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Expert: Alon Mandes - 11/3/2008


Question
A rectangular page is to contain 24 square inches of print. The margins at the top and the bottom of the page are each 1.5 inches. The margins on each side are 1 inch. What should the dimensions of the page be so that the least amount of paper is used?

Answer
Let's set the dimensions as x & y. The area of the paper is xy & it
is equal to 24. The effective area that is used is (x-2)(y-3).
("Note that the margins are from both sides left & right")
So our Function that to be minimized is M=(x-2)(y-3)=xy-2y-3x+6.
M=24-2y-72/y+6
M'=-2+72/y^2
M'=0 -> y^2=36 -> y=6 -> x=3

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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