Without changing the value of the fraction, the numerator and denominator of the following formulas are changed into integers. (1) x + 13y12x-y (2) 0.2A + 0.5b0.7a-b

Without changing the value of the fraction, the numerator and denominator of the following formulas are changed into integers. (1) x + 13y12x-y (2) 0.2A + 0.5b0.7a-b

① The original formula = 6x + 6 × 13y6 × 12x-6y = 6x + 2y3x-6y; ② the original formula = 10 × (0.2A + 0.5B) 10 (0.7a-b) = 2A + 5b7a-10b when the numerator and denominator of the fraction are multiplied by 6 at the same time

1. Given | A-1 | + √ ￣ B + 2 = 0, find the solution of the equation A / x + BX = 1
2. It is known that the factorization result of the quadratic trinomial 3x & # 178; + MX + n is (3x + 2) (x-1), and the value of M and N can be obtained
3. It is known that a, B and C are the three sides of △ ABC and satisfy the following conditions: A & # 178; + B & # 178; + C & # 178; - AB BC AC = 0
4. If a, B and C are trilateral of △ ABC, and a and B satisfy the relation | A-3 | + (B-4) & # 178; = 0, C is the largest integer solution of the inequality system {X-1 / 3 ＞ x-4, 2x + 3 ＜ 6x + 1 / 2, find the trilateral length of △ ABC

1 because | A-1 | + √ ￣ B + 2 = 0, so | A-1 | = 0 √ ￣ B + 2 = 0, so A-1 = 0, B + 2 = 0, so a = 1, B = - 22 two roots are - 3 / 2, the sum of 1 two roots is equal to - B / a = - M / 3 = - 3 / 2 + 1 = - 1 / 2, M = 3 / 2, the product of two roots is equal to C / a = n / 3 = - 3 / 2, n = - 9 / 23 A & # 178; + B & # 178; + C & # 178; - AB BC AC = 0

For any non-zero real number a, B, define the new operation "#" as follows: a # = A-B / ab. find: 2 # - 1 + 3 # - 2 + 4 # - 3 +... + 2008 # - 2007 + 2009 # - 2008

2#1=(2-1)/2*1=1/2=1/1-1/23#2=(3-2)/3*2=1/6=1/2-1/3(n+1)#n=(n+1-n)/[n(n+1)]=1/n-1/(n+1)2#1+3#2+4#3+...+2008#2007+2009#2008=1-1/2+1/2-1/3+1/3-1/4+.+1/2008-1/2009 ...