The tangent equation x2+y2 = R2 of the circle passing through the point P(x0, y0) on the circle is x0x+y0y = R2. The tangent equation between the circle passing through the circle (x-a) 2+(y-b) 2 = R2 and the point P(x0, y0) is (x0-a) (x-a)+(y0-b) (y-b) = R2. In addition, if the outer point M(x0, y0) passing through the circle x2+y2 = R2 is two tangents of the circle, the equation of the straight line where the two tangents are located is x0x+y0y = R2.
Extended data:
1 and the concept of high number
Higher mathematics refers to a more complicated part of mathematical objects and methods compared with elementary mathematics and secondary mathematics. Algebra, geometry and simple set theory in middle schools are called secondary mathematics, which is regarded as the transition between elementary mathematics in primary and secondary schools and advanced mathematics in universities.
2. High number content
Generally speaking, advanced mathematics is a basic subject formed by calculus, algebra, geometry and their intersection. The main contents include: series, limit, calculus, spatial analytic geometry and linear algebra, series, ordinary differential equations. Basic subjects for postgraduate examinations in engineering, science and engineering and finance.
3. Curriculum characteristics of advanced mathematics
Compared with elementary mathematics and secondary mathematics, mathematics is more difficult to learn, so it is often called "advanced mathematics" and "calculus" in textbooks, which is a different major of science and engineering. Students majoring in literature and history learn mathematics shallowly, and different majors in literature and history have different depths.
It is advanced mathematics that studies variables, but advanced mathematics does not only study variables. As for the courses related to "advanced mathematics", there are usually: linear algebra (advanced algebra for mathematics majors), probability theory and mathematical statistics (some mathematics majors study independently).
As a basic science, advanced mathematics has its inherent characteristics, namely, high abstraction, strict logic and wide application. Abstraction and calculation are the most basic and remarkable features of mathematics. Only with a high degree of abstraction and unity can we profoundly reveal its essential laws and make it more widely used.
Strict logic means that in the induction and arrangement of mathematical theory, whether it is concept and expression, or judgment and reasoning, we must use the rules of logic and follow the laws of thinking.