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Questions Answered

henpen:
Why does the wavefunction's second derivative not have to be continuous?
 updated one year ago
 10 replies
 1 Medal
Mathematics

JamesJ:
Hi guys.
If you have not already joined the edX bandwagon, there's a great upcoming physics course:
https://www.edx.org/courses/MITx/8.02…
 updated one year ago
 26 replies
 7 Medals
Mathematics

henpen:
Friction problem
 updated one year ago
 8 replies
 No Medals Yet
Mathematics

henpen:
Friction intuition help
 updated one year ago
 4 replies
 No Medals Yet
Mathematics

kr7210:
What is "lorentz invariant" ? Please explain with few examples.
 updated one year ago
 4 replies
 No Medals Yet
Mathematics

henpen:
Solve \[\sin(x+iy)=0\]
 updated one year ago
 9 replies
 2 Medals
Mathematics

henpen:
How to solve the equation \[e^x=e^{x}\]?
 updated one year ago
 2 replies
 No Medals Yet
Mathematics

henpen:
\[sin(x+iy)=sin(x)cos(iy)+sin(iy)cos(x)=sin(x)cosh(y)+isinh(y)cos(x)\]
\[sin(x+iy)^2=?\]…
 updated one year ago
 4 replies
 No Medals Yet
Mathematics

henpen:
Lagrangian mechanics: Is the definition \[\frac{\partial \mathbf{U}}{\partial \mathbf{x}}=\mathbf{F}\] arrived at only by minimising action…
 updated one year ago
 2 replies
 No Medals Yet
Mathematics

henpen:
Is the definition \[\frac{\partial \mathbf{U}}{\partial \mathbf{x}}=\mathbf{F}\] arrived at only by minimising action (that is, using the E…
 updated one year ago
 2 replies
 No Medals Yet
Mathematics

EasyMath:
Rewrite with only sin(x) and cos(x).
sin(3x)
 updated one year ago
 25 replies
 2 Medals
Mathematics

henpen:
Why does the determinant thing for working out cross products work?
 updated one year ago
 3 replies
 1 Medal
Mathematics

frx:
The equation for an ellipse is \[\frac{ x ^{2} }{ a ^{2} }+\frac{ y ^{2} }{ b ^{2}}=1\] and the foci is given by (c,0) where \[c ^{2}=a ^{2}…
 updated one year ago
 13 replies
 1 Medal
Mathematics

row:
Prove 2^(1/4)*4^(1/8)*8^(1/16)*16^(1/32) ... ∞ = 2.
Alternative view : http://www.wolframalpha.com/input/?i=2%5E%281%2F4%29*4%5E%281%2F8%29…
 updated one year ago
 3 replies
 2 Medals
Mathematics

cong1thanh:
How to find the Maclaurin series for f(x) using definition of a Maclaurin series: f(x) = ln(1+x)
 updated one year ago
 4 replies
 No Medals Yet
Mathematics

Youngster:
Wegman claims that their checkout scanners scan correctly 99.8% of the items sold. How many would you expect to buy, on average, to find one…
 updated one year ago
 16 replies
 1 Medal
Mathematics

TomLikesPhysics:
How do I find the total resistance of this network? Somehow I can not figure this simple network out.
 updated one year ago
 21 replies
 3 Medals
Mathematics

alyssababy7:
How can i verify
cot θ ∙ sec θ = csc θ?
 updated one year ago
 4 replies
 2 Medals
Mathematics

henpen:
Mathematically, prove that there are there no arbitrary constants required for the particular solution of \[Ly=f(x)\].
 updated one year ago
 10 replies
 No Medals Yet
Mathematics

mondalabhilash:
If the volume of a sphere increases by 72.8%, then
its surface area increases by how much and how ........
 updated one year ago
 3 replies
 1 Medal
Mathematics

hartnn:
If a line segment is cut into 3 parts, what is the probability that those 3 parts can form a triangle ?
 updated one year ago
 44 replies
 4 Medals
Mathematics

DDT:
Find minimum of : \sum_{k=1}^{n}a_{k}^{2}+\left(\sum_{k=1}^n a_k\right)^2. My teacher told me that I shoul use CauchySchwarz inequality. A…
 updated one year ago
 8 replies
 No Medals Yet
Mathematics

math_proof:
line integral over the vector field
 updated one year ago
 4 replies
 No Medals Yet
Mathematics

em.denning:
there are 17 questions on a moodle test, each of which consists of randomly drawing from three possible questions. how many different tests…
 updated one year ago
 7 replies
 1 Medal
Mathematics

DLS:
DE
 updated one year ago
 20 replies
 1 Medal
Mathematics

mandja:
How do you calculate the energy dissipated in air, when running (let's say you start from a point in space, you gradually increase speed and…
 updated one year ago
 13 replies
 2 Medals
Mathematics

ksaimouli:
http://www.chegg.com/homeworkhelp/questionsandanswers/lightshinespole30fthighballdroppedheightpoint20feetawaylightfastshado…
 updated one year ago
 15 replies
 2 Medals
Mathematics

BluFoot:
How can I simplify sin^5x? I need to write it in terms of sinx, sin(3x) and sin(5x).
 updated one year ago
 20 replies
 No Medals Yet
Mathematics

henpen:
Why do we still not have subsections for physics?
 updated one year ago
 6 replies
 5 Medals
Mathematics

henpen:
Are all \[y= \frac{1}{x^{2n1}} \] hyperbolas?
 updated one year ago
 2 replies
 No Medals Yet
Mathematics
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