If a and B are positive numbers, and a ≠ B, the proof is A2B + B2A > A + B
It is proved that: A2B + B2A − (a + b) = A3 + B3 − A2B − ab2ab = A2 (a − b) − B2 (a − b) AB = (A2 − B2) (a − b) AB = (a + b) (a − b) 2Ab. ∵ a and B are positive numbers, ∵ a + b > 0, AB > 0, and (a-b) 2 > 0, so (a + b) (a − b) 2Ab > 0, that is, A2B + B2A − (a + b) > 0, ∵ A2B
RELATED INFORMATIONS
- 1. An algorithm for comparing the sizes of two real numbers a and B is as follows: ditto
- 2. It is known that a and B are positive real numbers, and it is proved that (a + 1 / b) (B + 1 / b) ≥ 4
- 3. a. B is a real number if a After my research, I get a more appropriate answer Let a and B multiply by an integer m to make am + 2
- 4. Given a, B, x, y ∈ positive real number, prove (a ^ 2) / x + (b ^ 2) / Y ≥ (a + b) ^ 2 / (x + y)
- 5. Given that real numbers a and B satisfy a > b, prove: - A ^ 2-A < - B ^ 3-b
- 6. We know that a and B are positive real numbers, and a + B = 1, and prove that: [1 + 1 / (a ^ 2)] [1 + 1 / (b ^ 2)] is greater than or equal to 25 fast
- 7. If a and B are real numbers, prove that a ^ 2 + B ^ 2 is greater than or equal to 1 / 2 (a + b) ^ 2
- 8. Let F: X → - x2 + 2x be the mapping from real number set M to real number set n Let F: X → - x2 + 2x be the mapping from real number set M to real number set n. M = n = R, if for real number P ∈ n, there is no corresponding element in M, then the value range of P is determined
- 9. If three points P (1,1) a (2, - 4) B (x, - 9) are collinear, then x=___ ?
- 10. Given that real numbers x and y satisfy y = √ (the square of 3-x), we can find the range of (y + 1) / (x + 3) and (2x + 2Y)
- 11. If a times 4 / 15 = B divided by 4 / 15 = C, ABC is greater than 0, then (?) is less than (?) is less than (?)
- 12. How to compare the size of real number and imaginary number? For example, if you want to compare the sizes of 1 + 2I and 2, you can compare the modules of two numbers, that is, compare the sizes of 4 + 1 and 4 under the root?
- 13. As shown in the figure, in equilateral △ ABC, point D is the midpoint of BC side, and ad is taken as the edge to make equilateral △ ade. (1) find the degree of ∠ CAE; (2) take the midpoint F of AB side, connect CF and CE, and try to prove that quadrilateral afce is rectangular
- 14. As shown in the figure, in the equilateral triangle ABC, the midpoint D is the midpoint of the BC side. Take ad as the side to make the equilateral triangle ade. Calculate the degree of angle CAE
- 15. If 1 / X-1 / y = 3, what is the value of 5x + 2xy-5y / x-4xy-y Write process online = urgent!
- 16. In the triangle ABC, AB * BC = 3, and the area of the triangle ABC is between √ 3 / 2 and 3 / 2, then the value range of the angle between AB and BC AB and BC are vectors
- 17. The three sides a, B and C of triangle ABC satisfy the relation a ^ 2 + B ^ 2 + C ^ 2 + 338 = 10A + 24B + 26c. What triangle is it?
- 18. If three sides a, B, C of triangle ABC satisfy the condition: A ^ 2 + B ^ 2 + C ^ 2 + 338 = 10A + 24B + 26, then the height of the longest side of the triangle is___
- 19. If we know that the three sides of △ ABC are 5, 13 and 12, then the area of △ ABC is () A. 30b. 60C. 78d. Not sure
- 20. Given that the side length of △ ABC is a, B, C, and (B-C) 2 + (2a + b) (C-B) = 0, try to determine the shape of △ ABC