![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
How to find the angle of a vector? What is its formula? What's the formula for finding the angle between two straight lines?
The vector angle formula is cosa = (A.B) / (|a |b |)
Let the slope of the line be K1, K2
If the angle is a, then Tana = | (k1-k2) / (1 + k1k2)|
RELATED INFORMATIONS
- 1. Vector a = (3,2) when x is, vector b = (x, 1) is parallel to vector a
- 2. Given a = 4 and B = 3, when vector A / / vector B, find the product of a and B
- 3. Urgent! Let f (b) = B LNA - a LNB (b > a > e), then what is f '(b) equal to? Given that a and B are real numbers, and a > b > e, where e is the base of natural logarithm, we prove that a ^ b > b ^ a
- 4. The image of inverse scale function y = 2 / X is in the fourth quadrant, in which y increases with the increase of X
- 5. Write the inverse proportional function of Y increasing with X in every quadrant of an image___ ．
- 6. It is known that the image of the first-order function y = MX + N and the inverse scale function y = (3N-M) / X intersects at the point (1 / 2,2), and the value of M, N and another intersection point are obtained
- 7. It is known that the image of inverse scale function y = K / X passes through (1 / 2,8), and the line y = - x + B should pass through the image of inverse scale function (4, m) to find their inverse scale function and the function expression of the line
- 8. It is known that the linear function y = (3m + 1) x + M_ 2 1 if the function image passes through the origin, 2 finds the value of M. 2 if the function image does not pass through the second quadrant, 2 finds the value of M
- 9. Given that the image of a function y = 2mx + (6-3m & # 178;) passes through the origin and the second and fourth quadrants, then M=______
- 10. If the inverse scale function y = (k-1) x ^ k & # 178; - 5 passes through two or four quadrants, then k =?
- 11. It is known that vectors a and B are basic units, and vector a is multiplied by vector b = 0. If vector C satisfies | C-A-B | = 1, then the value range of | C | is
- 12. A square is an axisymmetric figure. It has an axis of symmetry ()
- 13. On the drawing with a scale of 1:2000, a rectangular building is measured to be 2.5cm long and 1.35cm wide. What is the floor area of this building? Solve with proportion
- 14. Why are there few stars when the moon is round and bright? Sometimes there are many stars, but there is no moon? Sometimes there are few stars when the moon is not bright? What does the moon and stars show?
- 15. If you extend the top and bottom of a right angled trapezoid by 5cm, the area will increase by 25cm, and then it will become a square. Find the area of the original right angled trapezoid
- 16. As shown in the figure, all quadrangles are squares, and all triangles are right triangles, Please find several figures in the figure so that the sum of their areas is exactly equal to the largest square area. Try to give more than two schemes
- 17. 48 pieces are arranged in a regular hexagon. The number of pieces on each side is equal. How many pieces are placed on each side?
- 18. Given that the image of quadratic function passes through the point (- 1,0) (5,0), the maximum value of the function is 6, find the analytic expression of the function
- 19. P is a point in the quadrilateral ABCD, connecting PA, Pb, PC, PD and AC, proving s triangle APC = triangle apb-s triangle APD Parallelogram ABCD
- 20. How to draw an elliptic equation with the Geometer's Sketchpad, it says to create one or more functions first,