<?xml version="1.0" encoding="UTF-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0"><channel><title><![CDATA[RSS Feed]]></title><description><![CDATA[RSS Feed]]></description><link>http://direct.ecency.com</link><image><url>http://direct.ecency.com/logo512.png</url><title>RSS Feed</title><link>http://direct.ecency.com</link></image><generator>RSS for Node</generator><lastBuildDate>Sat, 25 Apr 2026 01:36:00 GMT</lastBuildDate><atom:link href="http://direct.ecency.com/created/mathsolver/rss.xml" rel="self" type="application/rss+xml"/><item><title><![CDATA[[Math Talk #8] From Cone to Parabola - Properties and Usages]]></title><description><![CDATA[[1] Parabola - Interesting Properties and Usages 1. From Cone to Parabola Conic section is a curve obtained as the intersection of the surface of a cone with a plane. If the cutting plane is parallel to]]></description><link>http://direct.ecency.com/math/@mathsolver/math-talk-8-from-cone-to-parabola-properties-and-usages</link><guid isPermaLink="true">http://direct.ecency.com/math/@mathsolver/math-talk-8-from-cone-to-parabola-properties-and-usages</guid><category><![CDATA[math]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Wed, 22 Aug 2018 11:50:36 GMT</pubDate><enclosure url="https://images.ecency.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfg2U8e3M7jXKhnoznsrrhmdY?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[Physics and EE #4] Difference between Math and Physics]]></title><description><![CDATA[Difference between Math and Physics [1] Many of us just think physics as subfield of mathematics. But it is totally wrong. I will explain why. 1. Original Ampère's Circuital Law [2] In physics, Maxwell's]]></description><link>http://direct.ecency.com/physics/@mathsolver/physics-and-ee-4-difference-between-math-and-physics</link><guid isPermaLink="true">http://direct.ecency.com/physics/@mathsolver/physics-and-ee-4-difference-between-math-and-physics</guid><category><![CDATA[physics]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Sun, 19 Aug 2018 03:37:57 GMT</pubDate><enclosure url="https://images.ecency.com/p/6C2W1azD1rBs8i715pX3pAHYgtGre4Fsu6vSW2dcxF8gJSftEr8a1Bk?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[수학이야기 #2-2] 비둘기집의 원리 - 무리수와 무한급수 (마지막편)]]></title><description><![CDATA[비둘기집의 원리 - 무리수와 무한급수 (마지막) 지난 포스팅에 이어서 이번에는 무리수의 근사와 무한급수에 대해 다루어 보겠다. 이 부분은 지난 포스팅의 Section 2-3과 연결된다. 1. 무리수의 근사 먼저 임의의 무리수 와 자연수 &space;0" title="M > 0" /> 을 잡자. 집합 를 로 잡자. 단, 은 의 소수 (decimal) 부분을 나타낸다.]]></description><link>http://direct.ecency.com/kr/@mathsolver/3</link><guid isPermaLink="true">http://direct.ecency.com/kr/@mathsolver/3</guid><category><![CDATA[kr]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Sat, 18 Aug 2018 09:42:57 GMT</pubDate><enclosure url="https://images.ecency.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfFcUUPBck6wjMvaBD29sdogR?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[Math Talk #4] Pigeonhole Principle and Applications [2]]]></title><description><![CDATA[Pigeonhole Principle and Miscellaneous Applications (2) [1] Continuing our discussion of pigeonhole principle from Math Talk #3, I will post some miscellaneous applications of Pigeonhole principle. 1.]]></description><link>http://direct.ecency.com/math/@mathsolver/math-talk-4-pigeonhole-principles-and-applications-2</link><guid isPermaLink="true">http://direct.ecency.com/math/@mathsolver/math-talk-4-pigeonhole-principles-and-applications-2</guid><category><![CDATA[math]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Fri, 17 Aug 2018 14:34:00 GMT</pubDate><enclosure url="https://images.ecency.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfF4jpJbJeVmJzcuQDhqhM4Fo?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[Physics and EE #3] Does Magnetic Monopole Exist?]]></title><description><![CDATA[Does Magnetic Monopoles Exist? 1. Mathematical Background - Vector Identity Theorem 1. If is a scalar field and a vector field both of class , then Proof is just direct calculation, using . Theorem 2.]]></description><link>http://direct.ecency.com/physics/@mathsolver/physics-and-ee-3-does-magnetic-monopole-exist</link><guid isPermaLink="true">http://direct.ecency.com/physics/@mathsolver/physics-and-ee-3-does-magnetic-monopole-exist</guid><category><![CDATA[physics]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Fri, 17 Aug 2018 04:48:27 GMT</pubDate><enclosure url="https://images.ecency.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfExwCTELrJUVs2kjfsqgV3ft?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[수학 이야기 #2-1] 간단하지만 강력한 아이디어 - 비둘기집의 원리 (1편)]]></title><description><![CDATA[비둘기집의 원리 (1편) - 간단하지만 강력하다! 1. 비둘기집의 원리란 무엇인가? 그림을 보면, 5마리의 비둘기와 4개의 집이 있다. 4개의 집에 5마리의 비둘기를 알맞게 넣어주려면, 그 어떤 방법을 써도 적어도 하나의 집에는 2마리 이상의 비둘기를 넣어야 함을 알 수 있다. 이 것이 바로 비둘기집의 원리인데, 조금 더 수학적으로 써보면 다음과 같다. 비둘기집의]]></description><link>http://direct.ecency.com/kr/@mathsolver/2-1-1</link><guid isPermaLink="true">http://direct.ecency.com/kr/@mathsolver/2-1-1</guid><category><![CDATA[kr]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Thu, 16 Aug 2018 18:14:51 GMT</pubDate><enclosure url="https://images.ecency.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfEWszpjj63XakNeuH4srpVTj?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[Physics & EE #2] Gauss's Law in Electromagnetism]]></title><description><![CDATA[Gauss's Law for Electric Fields 1. Mathematical Background The Divergence Theorem, which states that for any compact space having piecewise smooth boundary , if the vector field is continuously differentiable]]></description><link>http://direct.ecency.com/physics/@mathsolver/physics-and-ee-2-gauss-s-law-in-electromagnetism</link><guid isPermaLink="true">http://direct.ecency.com/physics/@mathsolver/physics-and-ee-2-gauss-s-law-in-electromagnetism</guid><category><![CDATA[physics]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Thu, 16 Aug 2018 14:27:12 GMT</pubDate><enclosure url="https://images.ecency.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfERhByh34h7WZVnPDGQsdNog?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[Math Talk #3] Pigeonhole Principle and its Usage]]></title><description><![CDATA[Pigeonhole Principle in Mathematics 1. What is Pigeonhole Principle? First, let's look at the following figure. There are five pigeons, and four holes. Suppose we want to locate each pigeons into holes.]]></description><link>http://direct.ecency.com/math/@mathsolver/math-talk-3-pigeonhole-principle-and-its-usage</link><guid isPermaLink="true">http://direct.ecency.com/math/@mathsolver/math-talk-3-pigeonhole-principle-and-its-usage</guid><category><![CDATA[math]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Thu, 16 Aug 2018 08:53:57 GMT</pubDate><enclosure url="https://images.ecency.com/p/6C2W1azD1rBs8i715pX3pAHYgtGre4FkDGKyq8AjxTtvEkdriAsiza2?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[수학 이야기 #1] 주기 함수의 신기한 성질들]]></title><description><![CDATA[주기함수 (Periodic Functions) 수학에서 주기를 가진다는 것은 굉장히 좋은 조건이다. 왜냐하면 한 주기 내에서 함수의 변화를 관찰하는 것만으로, 정의역 전체에서의 함수의 변화를 알 수 있기 때문이다. 1. 들어가기에 앞서서 여기서 이야기할 모든 함수들은 정의역과 공역이 모두 실수 전체의 집합 로 한정한다. 즉 의 꼴을 가진다. 2. 주기함수란?]]></description><link>http://direct.ecency.com/kr/@mathsolver/1</link><guid isPermaLink="true">http://direct.ecency.com/kr/@mathsolver/1</guid><category><![CDATA[kr]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Wed, 15 Aug 2018 18:04:09 GMT</pubDate><enclosure url="https://images.ecency.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfDsqNVqUCx69ZE13TZuGM6Pf?format=match&amp;mode=fit" length="0" type="false"/></item><item><title><![CDATA[[Physics & EE #1] Phasor and its Usage]]></title><description><![CDATA[Phasor 1. Complex Plane In mathematics, a complex plane or sometimes called -plane, is a geometric representation of the complex numbers established by the real axis and the perpendicular imaginary axis.]]></description><link>http://direct.ecency.com/physics/@mathsolver/physics-and-ee-1-phasor-and-its-usage</link><guid isPermaLink="true">http://direct.ecency.com/physics/@mathsolver/physics-and-ee-1-phasor-and-its-usage</guid><category><![CDATA[physics]]></category><dc:creator><![CDATA[mathsolver]]></dc:creator><pubDate>Wed, 15 Aug 2018 13:34:48 GMT</pubDate><enclosure url="https://images.ecency.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfDsLitnTGpVF5Ns4mhVExScD?format=match&amp;mode=fit" length="0" type="false"/></item></channel></rss>