Mathematically simplified x 2 x x 1 x 2 x 4 x

1. Simplify. x+2/x-x-1/x-2)÷x-4/x

x-x+2/x-1/x-2)÷x-4/x

1/x-2)÷x-4/x

1/x*1/x-2/x-4/x

1/x²-6/x

2. [Fill in the blanks].

The average of 2,6,4,5,3 is 4

Variance = [(2-4) +6-4) +4-4) +5-4) +3-4) ]5=2

If 4x +mxy+y is a perfectly flat formula, then the formula can be changed to ( 2x) +mxy+y and then further to (2x+y). Resolve (2x+y) and (2x+y) = 4x +4xy+y

According to the principle of equality of correspondence, m=4 can be obtained

3. [Select].

The answer is D. The reason is that the deformation of B from left to right is a combination, not a decomposition factor, and the decomposition results of A and C from left to right are wrong. So choose D

The answer is D. Reason: The four corners of the rectangle are all 90 degrees, but the corresponding sides are not necessarily proportional, excluded; The corresponding sides of the diamond are proportional, but the corresponding angles are not necessarily equal, excluded; All isosceles trapezoidal corresponding angles are not necessarily equal, and the corresponding sides are not necessarily proportional, excluded.

Only the four corners of the square are 90 degrees, and each side must be proportional.

Summary. Hello dear, the answer is as follows.

9.Simplifying the algebraic formula |x-1|+|x-2|++x-2023|Combine.

Hello dear, the answer is as follows.

.（x²-4/x²-4x+4-x-2/x+2）÷x/x-2

(x-2)(x+2)/(x-2)²-x-2)/(x+2)]÷x/(x-2)

(x+2)/(x-2)-(x-2)/(x+2)]*x-2)/x

x²+4x+4-x²+4x-4)/(x-2)(x+2)*(x-2)/x

8/(x+2)

2.（a+2/a²-2a-a-1/a²-4a+4）÷4-a/a²-2a

(a+2)/a(a-2)-(a-1)/(a-2)²]4-a)/a(a-2)

a²-4-a²+a)/a(a-2)²×a(a-2)/(4-a)

1/(a-2)

1/(2-a)

3. x²+9x/x²+3x+x²-9/x²+6x+9

x(x+9)/x(x+3)+(x-3)(x+3)/(x+3)²

x(x+9)/x(x+3)+(x-3)/(x+3)

x²+9x+x²-3x)/x(x+3)

2x(x+3)/x(x+3)

x+1)²-4=x²-1

x²+2x+1-4=x²-1

2x=2x=1 x=1 The original equation is meaningless.

There is no solution to the original equation.

x+x+2=32

2x=30x=15

3x+4)(2x-3)+(3x-5)(2x-3)=(4x+1)(3x-5)

6x²-x-12+6x²-19x+15=12x²-17x-5

12x²-20x-12x²+17x=-5-3

3x=-8x=8/3

Xuefei, it's you again.

Original = (x 2-2x)[1 (x 2-2x)-1 (x 2-4x+4)].

Note: This section converts the two parentheses to the most direct multiplication.

1-(x^2-2x)/(x^2-4x+4)1-x(x-2)/(x-2)^2

1-x/(x-2)

This step can be done by directly changing to (x-2-x) (x-2)1-(x-2+2) (x-2).

It's up to you which method works best.

1-[1+2/(x-2)]

2/(2-x)

Bring x=3 in, and solve the original formula =-2

Simplify, then evaluate the defeat of the brigade: (1+1 x-2) x 2-2x+1 x 2-4, where x=-5

Defibrillation x-2+1) (x-2) (x+2) (x-2) (x-1) (x+2) (x-1).

If you don't understand anything about this question, you can ask it, and if you are satisfied, remember.

If you have other questions, click to ask me for help after this question, it is not easy to answer the question, please understand, thank you.

Good luck with your studies.