Recent content by Bohrok

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    Problem with Newton's second law

    Oh I know how to solve simultaneous equations; I just wanted to see if my work seemed alright :smile: Thanks! If no one else chimes in, I'll take it that they agree
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    Problem with Newton's second law

    Homework Statement In the following figure, the boy has a mass of 40kg, and the platform he is sitting on has a mass of 15kg. If the force of the board on the boy is 180N; a) Find the acceleration of the boy b) Find the reading of the scale...
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    How can I find the inverse equation for e^x/(e^x-1)?

    One more possible route to take is\frac{e^x}{e^x-1} = \frac{e^x-1+1}{e^x-1} = 1 + \frac{1}{e^x-1} However, That's not true in general for the product of a function and its inverse. What is true is that f(f-1(x)) = f-1(f(x)) = x
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    Simplifying a sum involving lnx

    ln(a) + ln(b) ≠ ln(a+b), but ln(a) + ln(b) = ln(ab). Try working with that.
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    Basic question about differential equation

    It's usually understood what the independent variable is in a given differential equation from the context; often it's either x or t when dealing with one independent variable.
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    What is the limit of (ah-1)/h as h approaches 0?

    If you use L'Hopital's rule, you'd have to differentiate with respect to h and not a (you always differentiate with respect to the variable under lim with l'Hopital's rule):\lim_{h\to 0}\frac{a^h-1}{h} = \lim_{h\to 0}\frac{\frac{d}{dh}a^h-1}{\frac{d}{dh}h} = \lim_{h\to 0}\frac{d}{dh}a^hwhich...
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    How Do You Solve This First Order Linear ODE?

    This isn't true; take a look at log/exponential rules.
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    C/C++ What are some simple and free resources for a C++ compiler?

    Thanks, that worked perfectly for me :smile:
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    How do I factor this trinomial

    Just try doing the long division again and you'll get a quadratic that you can factor; no need for any other tool to get the other factors.
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    C/C++ What are some simple and free resources for a C++ compiler?

    It's been years since I last programmed in C++ and I want to brush up on it over the next couple weeks. Problem is I have no idea what's out there that I could use for programming/debugging C++ programs; the compiler I used before came on a CD with the textbook, but now I'm completely on my own...
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    What Is the Rectangular Form of cos(-i)?

    Start with e^{i\theta} = \cos\theta + i\sin\theta and e^{-i\theta} = \cos\theta - i\sin\theta Then you add the equations and gete^{i\theta} + e^{-i\theta} = 2\cos\theta \Longrightarrow \cos\theta = \frac{e^{i\theta} + e^{-i\theta}}{2}
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    Finding a Quadratic Factor of z⁴+16

    I'm surprised no one mentioned the other way without using Euler! z^4 + 16 = z^4 + 8z^2 + 16 - 8z^2 = (z^2 + 4)^2 - 8z^2 This is a difference of squares that will factor and give you not just one but both real quadratic factors.
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    How can I find the roots of a polynomial like x^3-7x+6?

    You can also use the Rational Root Theorem to find the possible rational roots of a polynomial.
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