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Seven math problems-
1, a3? A3+(A3) 2 = 2a6。 Test center: the power of power and the power of products; Multiplication with the same base. Analysis: According to same base powers's law of multiplication, same base powers multiplies, the base is constant, and the exponents are added, that is, am? An = am+n. Solution: Solution: a3? a3+(a3)2,

=a6+a6,

= 2a6。 Comments: Test students' understanding and application of powers and powers with the same base.

2. Decomposition factor -ab3+A3b = AB (A+B) (A-B). Analysis: Firstly, the common factor AB is extracted, and then the residual polynomial is further decomposed by the square difference formula. Solution: Solution: -ab3+a3b,

=ab(a2-b2),

= ab (a+b) (a-b)。 3. Given that the top angle of an isosceles triangle is y and the bottom angle is x, the functional relationship between y and x is Y = 180-2x. Test center: list the functional relationship once according to the actual problem. Special topic: geometric problems. Analysis: According to the sum of a top angle and two bottom angles, it is 65433.

2x+y= 180,

Tidy it up: y = 180-2x. Comments: This topic makes use of the theorem of the sum of internal angles of triangles and the equidistant relationship between the properties of isosceles triangles.

A: Teacher Zhang.

∫AE∨CF

∴∠AEB=∠CFD

∫∠B =∠D,AE = CF。

∴△ABE≌△CDF.

So fill in ∠ B = ∠ D.5, as shown in the figure. When a telephone booth makes a call, the functional relationship between the telephone bill y (yuan) and the call time x (minutes) is graphically represented as a straight line. Xiaowen calls for 2 minutes, and 0.7 yuan pays. Xiaowen talks for 8 minutes, and 2.2 yuan pays. Test center: the application of linear function. Analysis: When the call time is less than 3 minutes.

The equations with the coordinates of point A and point B of (3,0.7) and (4,0 1) are established by the method of undetermined coefficient, and the functional relationship is obtained. Then substitute x=8 to get Y. Solution: Solution: According to the graph, if the call time is less than 3 minutes, you have to pay the phone bill, so Xiaowen calls for 2 minutes and 0.7 yuan pays 0.7 yuan.

Let's assume that the functional relationship between the telephone bill y (yuan) and the call time x (minutes) is: y = kx+B.

Because point A (3 3,0.7) and point B (4, 1) are both on y=kx+b, we substitute:

0.7=3k+b,1= 4k+B. Solution: k=0.3, b =-0.2.

Therefore, the functional relationship between phone bill y (yuan) and talk time x (minutes) is: y = 0.3x-0.2 (x ≥ 3).

When x=8, y=0.3×8-0.2=2.4-0.2=2.2 (yuan). 6. As shown in the figure, in △ABC, it is known that AD=DE, AB=BE and ∠ A = 80, then ∠ CED = 65438.

∴△ABD≌△EBD(SSS)

∴∠A=∠DEB=80

∴∠ ced =180-80 =100.7, y2+ky+4 is completely flat, then k = 4. Test center: completely flat. Analysis: First, write the original formula completely flat with the complete square formula, and then expand it.

∴y2+ky+4=(y 2)2=y2 4y+4,

∴ k = 4.8. Given that point p(2, m) is on the image of function y=2x- 1, the coordinate of point P is (-2, 3). Coordinates of points symmetrical about the X axis and the Y axis. Special topic: calculation problems. Analysis: When a point is on a straight line, the value of m can be obtained by substituting the coordinates of the point. When the point P is symmetrical about the Y axis, the vertical coordinate of the symmetrical point remains the same, but the horizontal coordinate is opposite. Solution: Substitute P(2, m) into y=2x- 1 to get m =

So, p (2 2,3),

Therefore, the coordinate of point P about the axis symmetry of Y is (-2,3) .9. In △ABC, the perpendicular line of AB intersects with AC at D, and if AC=5cm and BC=4cm, the circumference of △BDC is 9cm ... Test site: the nature of the perpendicular line in the line segment. Analysis: As shown in the figure, because DE bisects AB vertically, AD=BD can be obtained according to the nature of the midline of the line segment. From this, the perimeter of △BDC =BD+CD+BC=AD+CD+CB=AC+CB is deduced, and then the perimeter of △BDC can be obtained by using the known conditions. Solution: As shown in the figure, ∫DE divides AB vertically,

∴AD=BD,

∴△ circumference of ∴△BDC =BD+CD+BC=AD+CD+CB=AC+CB,

AC = 5 cm, BC = 4 cm,

The circumference of ∴△BDC is 9 cm.

So the answer to fill in the blanks is: 9 cm. 10. In the function y=xx- 1, the value range of the independent variable x is X ≠ 1. Test center: the range of function independent variables; Conditions for meaningful scores. Special topic: calculation problems. Analysis: the condition that the score is meaningful is that the denominator is not 0; The relation x- 1≠0 can be obtained by analyzing the original function, and the answer can be obtained by solving it. Solution: X- 1 ≠ 0 can be obtained according to the meaning of the question;

Get x ≠1;

So the answer is x ≠ 1.

1 1, if it is known that the function y=(m- 1) xm2+ 1 is a linear function, then m =- 1. Test center: definition of linear function. Special topic: calculation problems. Analysis: According to the definition of linear function, let m2 = 60.

Y is called a linear function of X (X is the independent variable and Y is the dependent variable).

So m2= 1,

Solution: m = 1,

M- 1≠0,

∴ m =- 1. 12, the monthly interest rate of education savings is 0.22%, and the existing income is 1000 yuan, then the functional relationship between the principal and interest y (yuan) and the number of savings months is Y = 2.2x+ 1000. Test center: list one according to the actual problem.

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