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Help! Help! Homework assigned by the teacher! Write a poem at the beginning of the sentence "Lin, Shu, Jie, Shi, Da, Jian, Bi". Ancient and modern poems are OK
I read books when I was dying
Books are killing me
The festival is endless
The end of the world
I won't take the college entrance examination
I can't think of it
I don't want to learn
Physics geniuses, a question assigned by the teacher in class, help me!
As like as two peas, I have just started my physics. I have just started studying physics. The second is the question: there is a river on the mountain, there is a boat in the upper reaches of the river, and there is a boat like the same in the lower reaches of the river. There is a block in the middle. (the distance between the armor and Otsuichi) is all fishing.
I'm sorry, of course. I should have caught it at the same time
The speed of a is v a + v current - V block
The velocity of B is v b - v current + V block
Because V block velocity = V flow, the relative velocity is the same
How to find the angular bisector vector of two vectors
Normalize the two vectors a and B respectively (that is, divide them by their own length respectively) to get the
C = A / | a |, d = B / | B |, then c + D is the original bisector of a and B
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