Mathematics X & # 178; - 4x + 1 = 0, X & # 178; + 3x + 1 = 0, use formula to solve equation

Mathematics X & # 178; - 4x + 1 = 0, X & # 178; + 3x + 1 = 0, use formula to solve equation

X & # 178; - 4x + 1 = 0, X & # 178; - 4x + 4 = 3 (X-2) ^ 2 = 3x-2 = root 3 X-2 = - root 3x = 2 + root 3x = 2 - root 3x & # 178; + 3x + 1 = 0x ^ 2 + 3x + 9 / 4 = 5 / 41 / 4 (3 + 2x) ^ 2 = 5 / 43 + 2x = root 5 3 + 2x = - root 5x = (root 5-3) / 2 x = - (3 + root 5) / 2

If the image of quadratic function y = ax & # 178; + BX + C passes through the point (- 2,10), and the roots of quadratic equation AX & # 178; + BX + C = 0 are - 1 / 2 and 2
If the roots are - 1 / 2 and 2, the analytic formula of the quadratic function is

Exercises for pursuing problems

The speed is 60 m / min, 75 m / min, 80 m / min respectively. A and B are in the East Village, C is in the West Village, and three people are facing each other at the same time. C meets a and then walks 12 points to meet a, and asks for things

In the plane, the distance from the moving point P to the point (1,0) is more than the distance from P to the Y axis. What is the point P trajectory equation of 1

Directrix-p / 2 = - 1 focus f (1,0)
p=2
y^2=2px=4x

Decomposition factors: (1) X2 (a-b) + 4 (B-A); (2) X2 (2x + y) 2-4x2y2

（1）x2（a-b）+4（b-a），=x2（a-b）-4（a-b），=（a-b）（x2-4），=（a-b）（x+2）（x-2）；（2）x2（2x+y）2-4x2y2，=x2[（2x+y）2-4y2]，=x2（2x+y+2y）（2x+y-2y），=x2（2x+3y）（2x-y）．

Someone works 24 days in a row and earns 190 yuan. He works all day from Monday to Friday with a daily salary of 10 yuan; he works half day on Saturday with a salary of 5 yuan; he doesn't work on Sunday with no salary. It is known that his work starts from one day in late March, and the first day of this month is Sunday, so what day is April when his work ends?

10 × 5 + 5 = 55 yuan, 55 × 3 + 25 = 190 yuan, 7 × 3 + 3 = 24 days. There are two full working days, one and a half working days in the extra three days, so his first day of working is Thursday. Since he starts working in late March, his first day of working is March 26. Because 31-26 + 1 + 18 = 24, his last day of working is April 18. A: the day when he finishes working is April 18

For example: s side = C bottom × h s table = s side + 2C bottom
1、 Find the surface area of the following cylinder
1. The bottom radius is 3 decimeters and the height is 2 decimeters
2. The diameter of the bottom is 1 meter and the height is 5 meters
3. The perimeter of the bottom is 18.84 decimeters and the height is 4 decimeters
2、 The length of a cylindrical chimney is 1.4m, and the diameter of the bottom circle of the chimney is 15cm. How many square meters of iron sheet is needed to make 50 such chimney?
3、 The utility model relates to a cylindrical tin tin can, the bottom radius of which is 6cm and the height is 5cm. How many square centimeters of tin is required to make 100 such cans? (the number of the resulting number is kept in the integer)
4、 There are 10 identical cylindrical columns in the hall of children's palace. The perimeter of the bottom surface of each column is 0.8m and the height is 6.6m. If one square meter of paint is painted, about 650g of paint is used, how many kg of paint is needed to finish painting these columns?
5、 The side view of a cylinder is a square with side length of 31.4cm

1. Bottom perimeter = 2 × 3.14 × 3 = 18.84, surface area = 18.84 × 2 + 3.14 × 9 × 2 = 94.22, bottom perimeter = 3.14 × 1 = 3.14, surface area = 3.14 × 5 + 0.5 × 0.5 × 3.14 × 2 = 17.273, radius = 18.84 △ 3.14 △ 2 = 3, surface area = 18.84 × 4 + 3.14 × 9 × 2 = 131.88

It is known that the new year's day in 2002 is Tuesday. What day is the new year's day in 2008!
You can also use another method to find the details.

There were 365 days in 2002-2007
(365 + 365 + 366 + 365 + 365 + 365) / 7 = 313, the remainder is 0
So:
New year's day in 2008 is Tuesday

The formula of mathematics in the sixth grade of primary school

What? Is it the area of the cylinder = perimeter of the bottom surface × height? Is it the volume of the cylinder = area of the bottom surface × height

What's 13 out of 4 times 3 out of 8

39/32