Recent content by RLBrown

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    MHB What are some interesting approximations of pi?

    My "Wagon Wheel Approximation of Pi" was featured at Wolfram on Pi day.
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    MHB Solve exponential equation x^4 = (5x+6)^2

    xxxx-(5x+6)(5x+6)=0 xxxx-25xx-60x-36=0 (x-a1)(x-a2)(x-a3)(x-a4)=0 a1a2a3a4 = ?
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    MHB Why is infinitesimal considered a number in mathematics?

    Click Here to get a (not rigorous) feel for hyperreal numbers.
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    MHB Quadratic Equation Help: Find 3 Points to Determine Answer

    Answer C (The graph of the solution set on (x,y) is two vertical lines.)
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    MHB How Does Constant Acceleration Affect Antelope Speed Over 70 Meters?

    Plot velocity versus time. The Area under the curve is the distance traveled for a given time interval. Using the formula for volume of a trapezoid... A =h (a+b)/2 Where: a=v b=15 m/s h=7 s A=70 m then 70=7(v+15)/2 140/7=v+15 v=20-15=5
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    MHB LCM & Meatloaf: Solving Tom's Problem

    12 is the LCM use as the common denominator. Do you see why?
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    MHB Find 4-adic Expansion of $\frac{1}{5}$ - Wondering

    Show that 1/5 is ... Using () to represent the repeated digits under the vinculum and everything base 4. Then show that 1/5 is ... (03)1.(0) Step 1: Calculate 4/5 (base 4) [FONT=Courier New] 0.3030... ------------ 11 / 10.0000... 3 3 --- 100 33...
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    MHB Vedic Math Method: Prove Conjecture Inspired by a Math Trick

    Below is a conjecture that I can't prove. It was inspired by a math trick for division when the (base 10) denominator ends in the digit 9. Can anyone help me out with a proof? - - - Updated - - - Here is an excell example,
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    MHB Is the Binomial Coefficient Test a Reliable Prime Indicator?

    I was examining the AKS and discovered this conjecture. Please prove the following true or false. Let n be an odd integer >2 then n is prime IFF $\left( \begin{array}{c} n-1 \\ \frac{n-1}{2} \\ \end{array} \right) \text{ $\equiv $ } \pm 1$ mod n
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    MHB Finding $\overline {AD} \times \overline {CD}$ in $\triangle APB$

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    MHB Must Have Math Books(That aren't "Text Books")

    Mathematical Thought from Ancient to Modern Times, Vols. 1,2 and 3 by Morris Kline
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    MHB What is the significance of Calculus of Variations in Classical Mechanics?

    Here is a link to lesson 2 of a Classical Mechanics on-line course at Stanford. At location 1:26:15 Lenny defines COV and introduces it's importance to Classical Mechanics. That application is calculation of "least action" in finding the trajectory of point masses in a system. This shows an...
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    MHB Prove Inequality: IMO $\frac{1}{x^4}+\cdots \geq \frac{128}{3(x+y)^4}$

    Do you mean $\dfrac{1}{x^4}+\dfrac{1}{4x^3y} + \dfrac{1}{6x^2y^2}+ \dfrac{1}{4xy^3}+ \dfrac{1}{y^4} ≥ \dfrac{128}{3(x+y)^4}$, given $x,\,y$ ?
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    MHB Right Triangle: Proving It's a Right Triangle

    Can one of the sides be negative?
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    MHB Software for Graphing Polynomials in Two Variables

    Graphing Calculator