May I ask if anyone knows the math problem, and the master is a little anxious, thank you Xi

Tang monks and apprentices walked on the boundless desert, they were hungry and tired, Zhu Bajie thought: How good it would be if there was a good meal! Sun Wukong is not as greedy as Bajie, Wukong just wants to drink a glass of water.

Sun Wukong thought about it, a family appeared in front of him, and there was a glass of milk on the table at the door, Sun Wukong hurriedly stepped forward and was about to drink this cup of milk, but the host said: "Great sage and slow, if you want to drink this cup of milk, you have to do a math problem." Sun Wukong thought, isn't it just a math problem, it is difficult for my grandson.

Sun Wukong agreed. The host asked: Pour a glass of milk, you first drink 1 2 full of water, then drink 1 3, fill up with water, and finally drink all this drink, and ask which one you drink more milk or water?

Why? Sun Wukong looked at it, scratched his head, and after a while, it came out, and drank this cup of milk. Students, do you know the answer? Try.

Answer) Sun Wukong is very smart, because there is only one cup of milk, and every time he adds water, he knows that he only needs to calculate the total amount of water added. And the amount of water added is 1 2 + 1 3 = 5 6 (cups). So it should be more milk to drink.

2010-07-05 Renjiao.com.

Remembering that her gray hair was lightened by the thickening twilight, she stood outside.

Stretch out with the quivering of the sleepers, drink the fun of battle with my buddies, the pike moves slowly, the dark clouds, the dark clouds haha.

The first step is to arrange the aircraft in full alignment, a(3,1).

In the second step, 1 vacant seat is inserted between the aircraft, and there is also 1 vacant seat on the left side of the leftmost aircraft and 1 vacant seat on the right side of the rightmost aircraft, so a total of 4 vacant seats are inserted. 10-4-3 = 3 empty slots remaining.

The third step is to insert the remaining 3 vacant seats into the aircraft between the aircraft or on the left and right sides, and each vacant seat insertion has 4 possibilities, that is, 4 to the 3rd power.

So, the number of all possible species is 4 a(3,1)=384.

If there is another 5 yuan and 1 cent, the two of them can buy 1 copy each.

Then the ** of each book is no more than 5 yuan and 1 point.

The maximum is $5.

My brother is short of 5 yuan, so my brother doesn't have a penny.

The ** of this book is 5 yuan.

The younger brother has 4 yuan, 9 jiao and 9 points.

The elder brother has no money, the younger brother has 4 yuan, 9 jiao and 9 cents, and the ** of the book is 5 yuan.

x+5=y+

y-x=y+xy<5y+xx book 5 yuan, the elder brother has no money, and the younger brother has yuan.

The elder brother has no money, but the younger brother has yuan, and the book price is 5 yuan.

The angle PBC is 60°, PB=PC=root number 2, SO triangle PBC is the equilateral triangle to find the height of the triangle PBC, the pyramid A-PBC, through the A perpendicular line, the intersection of the bottom surface is higher than a point D, the D point divides the height into two parts, the ratio is 1:2, find the PD, and then use the Pythagorean to find AD, AD is the height of the pyramid, the bottom equilateral triangle area is (root number 3) 4 sides of the square of the length, and the pyramid volume is 1 3 The base area times the height.

1.Red: Unit price of 5 pieces = Unit price of 3 pieces = 44 3

Red minimum = 71 7 + 16 = 513 yuan.

2.White: 5 yuan unit price = 3 pieces unit price = 53 3

White minimum = 87 7 + 20 = 629 yuan.

A total of at least = 513 + 629 = 1142 yuan.

It must be as cheap as possible to talk about the least amount of money.

Red sweatshirt 5 pieces a pack 7 + retail 16 yuan = 513 white sweatshirts 5 pieces a pack 6 + 3 pieces a pack 2 = 628 total: 513 + 628 = 1141 yuan, which is the least money.

1142 yuan is definitely not right.

When buying a white sweatshirt: if you buy 6 packs of 87 yuan bags and 2 packs of 53 yuan bags, the price is 628 yuan;

But if this calculation process were based on a high and small algorithm, I couldn't figure out a way!

4 Buy red at least to spend.

71 7 16 513 (yuan).

Buy white at least to spend.

87 6 53 2 628 (yuan).

The school will have to spend at least to buy this batch of sweatshirts.

513 628 1141 (yuan).

9 In the end, there are 2 people left, and it cannot be 1 person left.

Money needed to buy red:

Retail: 16 36 = 576 (yuan).

3 pieces in a pack: 36 3 = 12 (bag) 12 44 = 528 (yuan) 5 pieces in a pack: 36 5 = 7 (bag) ·· 1 (piece) 7 71 = 497 (yuan) 497 + 16 = 513 (yuan) (the cheapest).

Money needed to buy white:

Retail: 20 36 = 720 (yuan).

3 pieces in a pack: 36 3 = 12 (package) 12 53 = 636 (yuan) 5 pieces in a pack: 36 5 = 7 (package) ·· 1 (piece) 87 7 = 609 (yuan) 609 + 20 = 629 (yuan) (cheapest).

Total price: 513 + 629 = 1142 (yuan).

Hello: a -3a + 1 = 0

a²+1=3a

a+1/a=3

a+1/a)²=3²

a²+2+1/a²=9

a²+1/a²=7

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!

a +1 = 3a, substitution of the numerator, simplification. Then find the root formula to find a

If you look at 2x-3 as a whole, and the range of x is known, then multiply by 2 and add 3 to find the range of 2x-3 to know the maximum value.

I don't know how to ask.

Find the monotonic interval first, and then evaluate the range within the defined domain.