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

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

Your problem can be transformed into (1) to prove that there is at least one rational number x in (a, b),
If (1) is proved, it can be similar to substitution, if there is a rational number y in (a, x), then there is a rational number Z in (a, y)... Infinite
Now prove (1)
A and B are expressed in decimal form. By comparing the numbers on each digit of a and B, starting from the leftmost position until the numbers on the same position are different, in order to prevent the next digit from being too large, take another digit, intercept the two numbers, and then take the average value to get a rational number x, and a

It is known that a and B belong to positive real numbers, a + B = 1, and it is proved that (1 / A + 1)} + (1 / B + 1) > = 9
It's urgent,

A + B = 1 > = 2 √ AB, so AB = 2 * 4 + 1 = 9

It is known that a, B, X and y are positive real numbers, and 1A > 1b, x > y. The proof is XX + a > YY + B

It is proved that since a and B are positive real numbers and 1a ＞ 1b, B ＞ a ＞ 0, X ＞ y ＞ 0, BX ＞ ay is BX ay ＞ 0 (4) XX + a-yy + B = BX − ay (x + a) (y + b) > 0 (12 points)