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A machine has three gears, a and B mesh, C and B mesh, a and C do not mesh. If the diameter of a wheel is 200cm, the diameter of B wheel is 120cm, the diameter of C wheel is 250cm, and the angle a is 45 degrees, try to establish an appropriate coordinate system, and use the coordinate method to calculate the center distance of a and C wheels (accurate to 1cm)
This problem can be simplified to get a triangle. The a vertex of the triangle is placed at the origin, and the AC edge coincides with the X axis
Then, if the AB side is in the first quadrant, then the coordinates of point B are: (80 √ 2,80 √ 2)
According to the question, ab = 160cm, BC = 185cm, CA > 225cm,
Three points of mathematics required in senior one
High school mathematics compulsory 3 knowledge points Chapter 1 algorithm preliminary 1.1.1 algorithm concept 1, algorithm concept: in mathematics, the modern sense of "algorithm" usually refers to a kind of problem that can be solved by computer, is a program or step, these programs or steps must be clear and effective, and can be completed in limited steps
Three points of compulsory mathematics in senior one of people's Education Press
Algorithm preliminary statistical probability
Statistics and probability you need to know how to calculate the standard deviation of sample mean variance in sample space
Probability = sample occurrence / sample space
Mean = sample space / number of samples
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