Recent content by polak333

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    Finding Elasticity in Demand: Solving for p in the Demand Equation

    Thanks. So for: 1 = p/((20-p)/2)^2 · (p-20)/2 it would be: 1 < p/((20-p)/2)^2 · (p-20)/2 ... (work) ... 1 < (2p^2-40p)/((20-p)^2 p^2 - 40p + 400 < 2p^2 - 40p 0 < p^2 - 400 p > 20 or P < -20 Is that how it would look like?
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    Finding Elasticity in Demand: Solving for p in the Demand Equation

    Ok, never mind the post above, it was totally wrong already on the second step. Anyways, this time I think I got it: -1 = p/((20-p)/2)^2 · (p-20)/2 -1 = (2p^2-40p)/(20-p)^2 -(20-p)^2 = 2p^2 - 40p -p^2 + 40p - 400 = 2p^2 - 40p 0 = 3p^2 - 80p + 400 p = 20/3, 20 Did the same...
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    Finding Elasticity in Demand: Solving for p in the Demand Equation

    So I tried it: η = p / q · dq / dp 1 = p / q · dq / dp 1 = p/((20-p)/2)^2 · (p-20)/2 ... (some work) ... 1 = (2p-40)/(20-p)^2 20 - p^2 = 2p - 40 0 = -60 + 2p + p^2 p = -8.81 (inadmissible) p = 6.81 So therefore, 6.81 < p < 20. For those values of p, η is elastic. Does it look...
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    Finding Elasticity in Demand: Solving for p in the Demand Equation

    Do you mean η = p / q · dq / dp q = ((20-p)/2)^2 q' = (p-20)/2 .: η = p / ((20-p)/2)^2 · (p-20)/2 And since I know |η| must be greater than 1, then do I set η to something such as -2? or use -10? That's the only part I don't clearly understand because I could use any number, would it...
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    Finding Elasticity in Demand: Solving for p in the Demand Equation

    Homework Statement Derivatives and elasticity: The demand equation for a product is q = \left(\frac{20-p}{2}\right)^{2} for 0 \leq p \leq 20. a) find all values of p for which demand is elastic. Homework Equations Elasticity: \eta = \frac{p}{q} x \frac{dq}{dp} The Attempt at a...
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    How Much Should Rent Be Charged to Maximize Profit?

    Don't know if I understand. :confused:
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    How Much Should Rent Be Charged to Maximize Profit?

    Homework Statement A real estate office manages 50 apartments in a downtown building. When the rent is $900 per month, all the units are occupied. For ever $25 increase in rent, one unit becomes vacant. On average, all units require $75 in maintenance and repairs each month. How much rent...
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    Optimization Problem - Calculus

    Homework Statement A cylindrical shaped tin can must have a volume of 1000cm3. Find the dimensions that require the minimum amount of tin for the can (Assume no waste material). The smallest can has a diameter of 6cm and a height of 4 cm. Homework Equations V = \pi r^{2}h P = 2(...
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    Find Derivative of \frac{-3x^4}{(4x-8)^{1/2}}

    Ok, starting from 3 again: All I'm using is the Quotient Rule here. =\frac{-3x^{4}}{(4x-8)^{1/2}} =\frac{(-12x^{3})(4x-8)^{1/2} - (-3x^{4})(1/2)(4x-8)^{-1/2}(4)}{[(4x-8)^{1/2}]^{2}} =\frac{(-12x^{3})(4x-8)^{1/2}-(-3x^{4})(1/2)(4x-8)^{-1/2}(4)}{(4x-8)} =\frac{-12x^{3}(4x-8)^{1/2}...
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    Find Derivative of \frac{-3x^4}{(4x-8)^{1/2}}

    Homework Statement =\frac{-3x^{4}}{(4x-8)^{1/2}} Is it actually correct, I'm not sure if it's correct, still.Homework Equations Quotient Rule and Chain Rule The Attempt at a Solution =\frac{-3x^{4}}{(4x-8)^{1/2}}...
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    Derivative Homework: y=x4(2x-5)6

    Nevermind. I got it. Thanks for the help!
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    Derivative Homework: y=x4(2x-5)6

    y = (1-x2)3 (6+2x)-3 y' = 3 (1-x2)2 (-2x)(6+2x)-3 + (1-x2)3(-3)(6+2x)-4(2) y' = -6x (1-x2)2(6+2x)-3 - 6(1-x2)3(6+2x)-4 That's kind of the problem. I'm not sure how to take out < -6(1 - x2)2(6 + 2x)-4 >. In the 3rd line, there is a (6+2x)-3, how do you take out (6+2x)-4? Does the power...
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    Derivative Homework: y=x4(2x-5)6

    Thanks! Can you help me out with one more? y = (1-x2)3 (6+2x)-3 y' = 3 (1-x2)2 (-2x)(6+2x)-3 + (1-x2)3(-3)(6+2x)-4(2) y' = -6x (1-x2)2(6+2x)-3 - 6(1-x2)3(6+2x)-4 Not exactly sure what to do with this. I could possibly: y' = -6 (1-x2)(6+2x)-3[x-(1-x2)(6+2x)-1] or should I put...
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    Derivative Homework: y=x4(2x-5)6

    Homework Statement y =x4(2x-5)6 Homework Equations Product Rule & Power of a Function Rule The Attempt at a Solution y = x4(2x-5)6 y' = 4(x)3(1)(2x-5)6 + x4(6)(2x-5)5(2) y' = 4x3(2x-5)6 + 12x4(2x-5)5 The answer is: 20x3(2x-5)5(x-1) No idea where they get the 20x3 or the...
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