Narrate and prove the tangent length theorem

The tangent length theorem is: make two tangents of a circle from a point outside the circle, the distance from the tangent point to the point outside the circle is equal, and divide the angle between the two tangents equally

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8. Please introduce Einstein's famous equation E = MC2
9. How to read e = MC2 mass energy equation in English
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11. How to express the tangent length theorem
12. Tangent length theorem 1. In the trapezoid ABCD, ad ‖ BC, ∠ ABC = 90 ° the semicircle o with ab as diameter cuts CD at point M. if the trapezoid has an area of 10 square centimeters and a perimeter of 14cm, what is the radius of semicircle o? 2. The side length of square ABCD is a, AE cuts the semicircle with diameter BC to e, intersects DC to F, and finds CF: FD
13. What is the tangent length theorem?
14. Tangent length theorem
15. Two identical spherical conductors, suspended at the same point by thin insulated wires of 13 cm in length, have the same amount of charge (can be regarded as point charge). Due to electrostatic repulsion, the distance between them is 10 cm. The mass of each spherical conductor has been measured to be 0.6 g, and the amount of charge they carry is calculated. (known electrostatic constant k = 9 × 109 n · m2 / C2)
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17. What is the definition of Coulomb's law?
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