마스터프렙 No.1 유학생 전문 인터넷 강의 사이트

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Title	[Harim Yoo] Geometry questions
	Essential Guide to Geometry		1
Author	pur***	Date Posted	2024-06-12 오후 4:34:05
Hello Mr. Yoo, I have been watching your Geometry lessons and I have some questions: 1. In section 1.5 (Coordinate Plane), could you explain the concept of finding a midpoint using interior midpoints? For example, in the video, there was a line segment with points 1, 2, 3, and 4, with 2 and 3 being the interior midpoints. Why do I have to do 1/2 x 1 + 1/2 x 4 = 2.5 in this scenario? 2. In the Think Through 120 Problems Book, could you explain how to solve problem 5? 3. In section 3.2 (Truth Tables), if the hypothesis (p) is false, why is the conclusion (q) always true?' Thank you!
2024-06-13 오전 11:34:44 Hello, 1. The interior formula uses the idea of mass point geometry. For example, the midpoint stays exactly the same distance away from 1 and 4. So, we give weights of 1 and 1 to "1" and "4". Then, the interior point gives relative weight on 1 and 4. In other words, 1/(1+1) * 1 + 1/(1+1) * 4 = 2.5 would work. You can try the same thing for 2. Let's find 2 real quick using interior point. Give weight 2 to point 1 and weight 1 to point 4. Think about seesaw effect. 2 = 2/(1+2) * 1 + 1/(1+2) * 4 = 2/3+4/3=6/3=2. 2. Choose one vertex out of 6 in 6 ways. Choose the second vertex out of remaining 5 points in 5 ways. We have 30 edges connected. But, one edge has been counted twice in this way. For instance, AB has been counted BA. That's not a good sign. So we divide it by 2 to get 15. Yay! 3. If hypothesis is true, there is no way that we can say anything about the conclusion. So, we safely conclude that q is true. Think about it otherwise. Do we have any reason to say q is false? Well, there might not be. So we say q is true until we find some evidence saying otherwise. Yay!