Recent content by erik05

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    How Do You Calculate the Ionization Energy of Hydrogen Using Quantum Mechanics?

    Hello everybody, just wondering if anyone could point me in the right direction for this question. Please and thanks. 1) Since the ionisation process takes an electron from its ground state to the zero level of the energy scale, the ground state energy calculated for the electron of the...
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    How can I solve this integral using substitution and integration by parts?

    I seem to be having trouble on this one integral.Any help would be much appreciated. \int 3x \sqrt{5-2x} dx I'm assuming the substitution rule applies to this so I have u=5-2x. Then du=-2dx And now I'm stuck. How can I get 3xdx to equal -2dx? Please and thanks.
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    Intervals of Increase and Decrease for e^x = e^-2x

    I can't believe I didn't get that...thanks.
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    Intervals of Increase and Decrease for e^x = e^-2x

    Stupid question...but why to the exponent of 3?
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    Intervals of Increase and Decrease for e^x = e^-2x

    Hello all. Really quick question here...What are the intervals of increase and decrease for y= e^x = e^-2x. I found the first derivative : y'= e^x-2e^-2x and set it equal to 0 but that's where I got stuck. How would you solve for x? I know that the answer is (ln2)/3 but how would you get there...
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    Calculus: Applications of Trig

    I guess I'll just assume that the book is wrong.
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    Calculus: Applications of Trig

    That's what the answer in the back of the book says. It's weird because you'd think it would be in rad/s or degrees/s...
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    Calculus: Applications of Trig

    I get the same answer too except that it's negative, which makes sense since it's decreasing. This is what I did: sin\theta= \frac {40}{80} and taking the inverse of that I get 30 degrees. From before: \frac {dx}{dt}= -80sin\theta \frac {d\theta}{dt} \frac {d\theta}{dt}= \frac...
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    Calculus: Applications of Trig

    That's the thing, I never know what to start with so I really don't have that much work. I'm assuming that all of these questions are involving triangles and that the cosine law could come in handy for a few of them.
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    Calculus: Applications of Trig

    Hello all. I have a test on these type of questions coming up soon :grumpy: and this is about the time when frustration sets in since I'm not very good at these questions. If anyone could show me how to do them so I could study off it then you would be my hero. 1) A wall of height 8 m...
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    What is the Limit of the Tangent Function as x Approaches 0?

    This is going to sound really pathetic but no, we haven't the taylor series either.
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    What is the Limit of the Tangent Function as x Approaches 0?

    Sorry, I haven't learned l'hopitals rule yet and we're not suppose to use it for these questions.
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    What is the Limit of the Tangent Function as x Approaches 0?

    Hello all. I missed a class in calculus so I didn't get the notes on this so if anyone could explain this question for me, it would be much appreciated. \lim_{x \rightarrow 0} \frac {tanx}{4x} = \frac {sinx}{cos4x} ? Not really too sure if I manipulated the equation right. Any hints...
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