The origin of Spring Festival Customs of the Spring Festival

According to China's Lunar, the first day of the first lunar month yen ancient name, Yuan-chen, a copy, which is commonly known as Day of the Republic. January 1st called the Lunar Spring Festival.

Define a new operation symbol with "", for any rational number a, B, there is a b = A2 + B2, then (- 3) * 5 =?

According to the definition, (- 3) * 5 = - 3) ^ 2 + 5 ^ 2 = 9 + 25 = 34

What is 0.08 times 100%?
What's 800 times 100%?

Because 100% = 1

Given x = root 3-1, find (3-2x & sup2; - 4x) / (X & sup2; + 2x-1)

x+1=√3
square
x²+2x+1=3
x²+2x=2
The original formula = [3-2 (X & sup2; + 2x)] / [(X & sup2; + 2x) - 1]
=(3-4)/(2-1)
=-1

The beverage factory recycles water bottles and stipulates that every 7 empty bottles can be replaced by 2 bottles of soda. Xiaogang bought 15 bottles. How many bottles can he drink?

15 + (15 / 7) + (2 / 7) bottles

x> 0, Y > O, x + 2Y + 4xy = 8, what is the minimum value of XY

8/（4+2*2^1/2）

Xiao Li and some children went to a fast food restaurant for dinner. They bought 10 hamburgers and chips, which cost 76 yuan. How many hamburgers and chips?
Hamburger 10 yuan, French fries 6 yuan

If the hamburger is x, the French fries are 10-x
10x+6(10-x)=76
10x+60-6x=76
10x-6x=76-60
x=4
10-x=6
So 4 hamburgers and 6 French fries, please accept

Known: a + 2B = 0, prove a ^ 2 + 2Ab (a + b) + 4B ^ 2 = 0

a^2+2ab(a+b)+4b^
=a^2+4ab+4b^2+2ab(a+b)-4ab
=(a+2b)^2+2ab(a+b-2)
=2ab(a+b-2)
Since it is impossible to prove 2Ab = 0, it is impossible to prove a + B-2 = 0
So it can't be proved with known conditions
a^2+2ab(a+b)+4b^2=0

The distance between a and B is 200 kilometers. Car a runs 40 kilometers per hour from a to B. after car a runs for 1.5 hours, car B runs 30 kilometers per hour from B to A. how long does it take car B to meet car a?

Set X hours
30x+40x+60=200
70x=140
x=2

(1-2)(2-3)(3-4).(2001-2002)(2002-2003)

(1-2)*(2-3)*(3-4).*(2001-2002)*(2002-2003)
=（-1)^2002
=1

The origin of Spring Festival Customs of the Spring Festival