It is known that the equation x + 2 of X + 1 minus X-1 of X is equal to x plus x minus 2 of A (1) If there is no solution to the original equation, the value of a can be obtained. (2) if the number called by the hospital is an integer, the value range of a can be obtained

It is known that the equation x + 2 of X + 1 minus X-1 of X is equal to x plus x minus 2 of A (1) If there is no solution to the original equation, the value of a can be obtained. (2) if the number called by the hospital is an integer, the value range of a can be obtained

(x + 1) / (x + 2) - X / (x-1) = A / (x ^ 2 + X-2) (x ^ 2-1-x ^ 2-2x) / (x + 2) (x-1) = A / (x + 2) (x-1) a = - 2x-1 (1): when there is no solution, find a x = - 2, a = 3, x = 1, a = - 3 (2): the solution is an integer, find a a a = - 2x-1, 2x = - A-1, x = - (a + 1) / 2, X is an integer, a + 1 is an even number, a is an odd number (not equal to plus or minus 3)

Straws, chopsticks, newspapers, tape how to build a five centimeter distance from the ground can bear the weight of a person's bridge

First fold the newspaper into a wave shape (the depth of the fold in the middle should be the same as the thickness of the chopsticks), then paste the adhesive tape horizontally on the newspaper and fill it up (also in the fold). Connect the chopsticks with a straw and put them in the fold of the newspaper
I don't know if it's OK. I haven't tried it. It depends on my guess. Don't scold me if you fail

X - (0.5x + 18) - (0.5x-5) = 40, how much is x equal to?

x-(0.5x+18)-(0.5x-5)=40
x-0.5x-18-0.5x+5=40
Then - 13 = 40
So the original equation has no solution

The distance between a and B is 10 kilometers. A starts for one hour and then B starts. A is behind B. they walk in the same direction. It is known that a walks 5 kilometers per hour
B walks 4 kilometers per hour. How many hours after B leaves, is he overtaken by a

5(x+1) = 4x + 10
X = 5 hours

Given the quadratic power of a + AB = 10, the quadratic power of B - AB = 7, then the quadratic power of a + the quadratic power of B =, the quadratic power of a + the quadratic power of 2ab-b

a²+ab=10,b²-ab=7,
a²+ab+b²-ab = a²+b² = 10+7 = 17
a²+ab-（b²-ab） = a²+2ab-b² = 10-7 = 3

Factorization (20:13:22)
The method of extracting common factor is as follows
1、3a(x+y)-6b(y-x)=
2、(m-n)³+2n(n-m)²=
 

3a(x+y)-6b(y-x)=3(ax+ay-2by+2bx)
(m-n)³+2n(n-m)²=(m-n)^2(m-n+2n)=(m-n)^2（m+n）

The store brought in 8 cases of apples, each of which had the same weight. After 15 kg was taken out of each case, the remaining weight was exactly equal to the weight of the original two cases. How many kg were the original apples in each case?

15X8➗（8-2）=20

(2 of a-2b + 1 of a-b) * (3a-4b) (a + b) a-2b
(B-C) (C-A) a + B - (a-b) (A-C) B + C - (a-b) (C-B) C + A

Let the pure imaginary number Z satisfy | Z | = 1, Z ^ 2 + 2Z + 1 / Z

z=cost+isint
cos2t+isin2t+2cost+2isint+cost-isint

100 kg of apples from fruit shop is 2 / 3 of pears. How many kg of pears are there?
______ *2/3=_____

100 divided by 2 / 3 = 100 times 3 / 2 = 150 kg