Recent content by Wardlaw

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    Is (a+b)^2 Always Equal to a^2+2ab+b^2?

    Is p+q+r=p+q+s never valid?
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    Is (a+b)^2 Always Equal to a^2+2ab+b^2?

    Math problem! Homework Statement Is (a+b)^2 ALWAYS equal to a^2+2ab+b^2? Homework Equations The Attempt at a Solution
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    High School Smoke Signals vs Sound Signals - Propagation Distance

    Aren't you a clever cookie
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    High School Smoke Signals vs Sound Signals - Propagation Distance

    Why is it that smoke signals can propagate information over longer distances than sound signals?
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    Simultaneous equations using exponential functions

    Yes, i tried this. However the answer i get does not match the answer set in the textbook!
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    Simultaneous equations using exponential functions

    Homework Statement Solve the following equations using simultaneous equations Homework Equations 32x\times23y=17 4x\times5y=37 Appologies for the bad equation set-up. The large 'x' is a multiplication sign. The Attempt at a Solution My attempt was to divide both of the...
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    Calculating a and b in 3D Unit Vector Question for Test Prep

    No need! Done it.
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    Calculating a and b in 3D Unit Vector Question for Test Prep

    I was given the question, If u=ai+2j+4k and v=3i+bj+k, calculate a and b in a textbook from school (revision for a test). Any thoughts?
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    What is the stopping potential for a wavelength of 230nm?

    Modern Physics question! Homework Statement When radiation of wavelength 350nm is incident on a surface, the maximum kinetic energy of the photoelectrons is 1.2ev. What is the stopping potential for a wavelength of 230nm? Homework Equations \phi=hc/\lambda-eV0( V0= V 'nought') I am...
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    De Moivre's Theorem (-12-5i)^-3

    Homework Statement Using De Moivres Theorem, solve (-12-5i)^-3 Homework Equations The Attempt at a Solution The solution i get for this problem is different from the one given in the exercise text. This is 1/2197cis(8.241) Note: cis is equivalent to cos(\Theta)+isin(\Theta)
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    Cosh(2z) Equals Cosh^2(z) Plus Sinh^2(z)

    Solved:biggrin:
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    Cosh(2z) Equals Cosh^2(z) Plus Sinh^2(z)

    Oh yeah you are correct, my mistake. I can't even read my own working :) How exactly do you go about solving thi problem?
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    Cosh(2z) Equals Cosh^2(z) Plus Sinh^2(z)

    Yeah. I tried using the standard form for these expressions, when considering the RHS. I am then left with a quarter e^2z. Could you check this please?
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    Cosh(2z) Equals Cosh^2(z) Plus Sinh^2(z)

    Show that cosh(2z)=cosh^2(z)+sinh^2(z) ?
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    Complex Number Help: Find Modulus & Principle Argument

    Complex number help! Homework Statement Find the modulus and principle argument of 1/(-sqrt(3)+i) Homework Equations The Attempt at a Solution I attempted this solution by using the complex conjugate, and as i^2=-1, i eventually ended up with 4 in the denominator. Any suggestions?