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bio website problemasteoremas.wordpress.c…
location Queluz, Portugal
age 63
visits member for 4 years, 3 months
seen 5 hours ago

I am a retired electrical engineer, Portuguese. My math blog is Problemas e Teoremas.


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revised I Don't Understand This Arc Length Formula
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answered I Don't Understand This Arc Length Formula
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revised How to prepare myself for an advanced trignonometry exam
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revised Help finding the residue of $1/(z^8+1)$
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comment Why is trigonometry important in calculus?
Short answer: engineering can be viewed as applied physics, as such trigonometry and calculus are used in all cases where it's used in Physics.
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revised Help finding the residue of $1/(z^8+1)$
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awarded  Custodian
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reviewed Leave Open Why is trigonometry important in calculus?
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revised Help finding the residue of $1/(z^8+1)$
Added computation of the sum of residues
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revised How to prepare myself for an advanced trignonometry exam
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revised How to prepare myself for an advanced trignonometry exam
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revised How to prepare myself for an advanced trignonometry exam
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revised How to prepare myself for an advanced trignonometry exam
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answered How to prepare myself for an advanced trignonometry exam
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comment How to evaluate the trigonometric integral $\int \frac{1}{\cos x+\tan x }dx$
To the downvoter. This method, although general for this type of integrand, is not fast compared to a good particular one. I think I've not made any mistake, because I've just confirmed that the derivative of the final expression is the integrand given in the question.
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revised Help finding the residue of $1/(z^8+1)$
edited body; edited tags
Nov
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revised Help finding the residue of $1/(z^8+1)$
Simplified the exposition
Nov
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revised Help finding the residue of $1/(z^8+1)$
Fixed two typos
Nov
23
answered Help finding the residue of $1/(z^8+1)$
Nov
23
revised Divergence and Convergence of improper integrals of $1/x$ and $1/x^2$
edited tags; edited title