The multiplication of algebraic expressions in the second chapter of mathematics in the second volume of the first day of junior high school
First, multiple-choice questions (30 points)
1, the following operation is correct ()
A.x3+x = x4； b .(x2)3 = X6； c . 3x-2x = 1； D. (a-b)2=a2-b2
2, in the following, the operation result is a2- 16b2 is ().
A.(-4 b+ a)(-4 B- a)； b .(4 b-a)(-4 b-a)； c .(-4 b+ a)(4 B- a)； D. (4b+a)(4b-a)
3. Calculation: (-2x2) The result of 3 is ()
A.-2x 5； b .-8x 6； c .-2x 6； d .-8x 5；
4. If x2+ax-24=(x+2)(x- 12), the value of a is ().
A.？ 10; b .- 10； c . 14； d .- 14；
5, in the following formula for completely flat way is ()
A.a2+a b+B2； b . a2+2a+2； c . a2-2 b+B2； ; d . a2+2a+ 1；
6. Calculation: 0.042003? (-52003)2 De:()
A. 1; b .- 1； c； d .-；
7. If (am+1bn+2) (a2n-1b2m) = A5B6, then the value of m+n is ().
A. 1; b . 2； c . 3； d . 4；
8. Given that x-y=3, X-Z =, the value of (Y-Z) 2+5 (Y-Z)+equals ().
A.； b； c； d . 0；
9. As shown in the figure, the side length of a square is a, and a semicircle is drawn with each side as the diameter in the square, so the area of the shaded part is ().
A.； b；
C.； d；
10, given that the value of algebraic expression 3y2-2y+6 is 8, then the value of algebraic expression y2-y+ 1 is ().
A. 1; b . 2； c . 3； d . 4；
Two. Fill in the blanks (24 points)
1 1, simplified: 6a6? 3a3=。
12. It is known that when x= 1, the value of 2ax2+bx is 3, and when x=2, the value of ax2+bx is.
13, if x2n=3, then x6n=.
14, calculation: (-2m- 1) 2=.
15. If (2a+3b) 2=(2a-3b) 2+ () holds, the formula in brackets is.
16, calculated according to the following procedure: input x=3, and the output answer is.
Liang Xiao and Xiao Ming are playing games. They each quoted an algebraic expression. The business formula must be 2xy, and Xiaoming quoted x2-y, so the division formula of Xiao Liang newspaper should be.
18. Divide a 20cm long iron wire into two sections, and each section forms a square. If the area difference between two squares is 5cm2, the lengths of the two iron wires are respectively.
Iii. Answering questions (46 points)
19, (12 points) Calculate the following questions:
( 1)(a+3)(a- 1)+a(a-2)(2)
(3) (4)(x-y+z)(x-y-z)
20.(6 points) Simple calculation with square difference formula: 98? 102+4
2 1, (6 points) simplify first, and then evaluate: (2x+3y) 2-(2x+y)(2x-y)+ 1, where x=, y=.
22.(6 points) Divide the known polynomial A by the polynomial x2-2x- to get the quotient formula 2x and the remainder formula x- 1.
Find this polynomial a.
23.(6 points) There is a square lawn with a side length of 2 meters in the square. After the same planning, the north-south direction will be shortened by 3 m, and the east-west direction will be lengthened by 3 m, so the area of the reconstructed rectangular lawn will become larger or smaller than the original area, which is explained by calculation.
24.( 10) Read the material and answer the question: If m2+2mn+2n2-6n+9=0, the value of.
Solution: m2+2mn+2n2-6n+9=0, that is, (m+n2)+(n-3) 2=0.
? n=3，m=-3？ = =
According to your observation, discuss the following questions:
(1) If x2+4x+y2-8y+20=0, then.
(2) If x2-2xy+2y2+2y+ 1=0, find the value of x+2y.
(3) Try to prove that no matter what rational numbers X and Y take, the value of polynomial x2+y2-2x+2y+3 is always positive.
The multiplication test questions of algebraic expressions refer to the answers in the second chapter of junior one mathematics.
1. 1，b； 2、B； 3、B； 4、B； 5、D；
6、A； 7、C； 8、D； 9、A； 10、B；
Second, 1 1,18a9; 12、6; 13、27; 14、4 m2+4m+ 1； 15、24ab
16、 12; 17、x3y-2xy 2； 18、 12cm、8cm
Iii. 19, (1) Original formula = 2a2-3; (2) The original formula = a11b3;
(3) The original formula =-7x6y4+7x5y3-49x4y3; (4) Original formula = x2-2x y+y2-z2
20、 10000;
2 1, the original formula =12xy+10y2+1,when x=, y=, the original formula =
22. This polynomial A=
23. It's getting smaller.
24、( 1) ? x=-2，y = 4； ? =-2;
(2)x2-2xy+2y2+2y+ 1=0，√
? y=- 1，x =- 1； ? x+2y =-3；
(3)x2+y2-2x+2y+3 = x2-2x+ 1+y2+2y+ 1+ 1 =
∫(x- 1)2？ 0，(y+ 1) 2？ 0,
? The minimum value of is1; ? The value of x2+y2-2x+2y+3 is always positive.
People who have read the multiplication questions and answers of algebraic expressions in the second chapter of the second volume of junior high school mathematics also read:
1. Hebei Education Edition Sixth Grade Last Term Mathematics Examination Paper
2. Test paper and answer of Unit 3 in the first volume of sixth grade mathematics.
3. Hebei Education Edition, the fifth grade, the first volume, the third unit of mathematics questions and answers.
4. Hebei Education Edition, Grade Six, Volume One, Mathematics Mid-term Examination Paper.