The solution of a problem, the solution of this problem?

The original amount of wine in the pot is required, and the change of the wine in the pot and the final result - three times multiplied (multiplied by 2) and quantitatively minus (** bucket) and light. To solve this problem, we generally start from the result after the change, and use the mutual inversion relationship of multiplication and division, addition and subtraction, and gradually reverse the reduction. "Three encounters with shops and flowers, drink up the wine in the pot", It can be seen that there is a wine bucket in the pot when the three encounters the flower, then there is a wine bar 1 2 buckets when the three encounters the shop, then, there is a wine 1 2 + 1 bucket when the second encounter flower, and there is a wine (1 2 + 1) 2 bucket when the second encounter shop, so there is wine (1 2 + 1) 2 + 1 bucket when the flower is encountered, and there is wine when there is a store when the store is encountered, that is, the calculation formula of the original wine in the pot is.

1 2 + 1) 2 + 1] 2 = 7 8 (bucket) Therefore, there were originally 7 8 buckets of wine in the pot.

The main point of the above solution is reverse reduction, which can also be represented by schematic diagram or line diagram.

Of course, if the problem is solved by algebraic methods, the quantitative relationship of this problem is more explicit. Set the original wine x bucket in the pot, and list the equation according to the title.

2[2（2x-1）-1] -1=0

Solution, get x=7 8 (bucket).

As you wrote, if it is required that x is any value, and the inequality is constant, then the image of the inequality is open upward, then a2-3a+2>0, find a>2 or a, and at the same time, it is required that δ, the image has no intersection with the x-axis, and it can be proved that above the x-axis (a-1)2-8(a2-3a+2), find a>15 7,a combined, a>15 7,a<1

(1) According to the cosine theorem, cosc -1 2, that is, the angle c is greater than 90°, and the solid triangle abc is an obtuse triangle.

2) SINC = 3 2 and triangle abc area 1 2 (absinc) 15 3 4 can be calculated from COSC

Solution: The height of the first Hui Kong bounce is 2 3 of the falling height, so the first bounce is 20 3 meters, and the second height is 20 3 of the destruction of 2 3, which is 40 9 meters.

The title is wrong, and on the right side of the equation is the item's **.

So there's no money you can't find.

If a customer buys a 1 piece and prefers to give 6 pieces, then there is no way to find it.

There are countless and many cases, because the amount of money can go up indefinitely, so there is no maximum value.

The simplest solution to this problem is to use a right triangle to connect OA and OP, if OA is perpendicular to PA, then the triangle OPA is a right triangle and APO=60°OA=4 so there is PA=4*3

The correct answer is B

If we look for key sentences and main words in generalization questions, we can see that the whole paragraph is a fractional structure, and it is difficult to find key sentences. This article gives two examples of how Russian and German scientists have used science to improve the process of disposing of garbage to a higher level. The main words are "technology" and "garbage disposal", and in summary, the answer is item b.

It is recommended to find such question types from the official website of Huatu.

Let the volume of each bottle of solution be a, then the volume of alcohol in bottle 1 is 5 12a, and the volume of water is 7 12a; The alcohol in bottle 2 is 1 6a and the water is 5 6a. After mixing, the total volume is 2a, with a total of alcohol (5 12a + 1 6a) = 7 12a, water (7 12a + 5 6a) = 17 12a. Therefore the ratio of alcohol to water is (7 12a).

or lead (17 12a) = 7:17

2CO+O2=CO2 (Reaction 1).

That is to say, after the reaction of 2 volumes of CO with 1 volume of O2, 2 volumes of CO2 are produced, and the total volume of gas before and after the reaction decreases by 1. Now that the volume is reduced by 4, there is 4 ml of O2 involved in the reaction and 8 ml of CO involved in the reaction

By preparing the solution with sodium hydroxide, the volume is reduced by 10ml, which means that the total volume of CO2 after the reaction is 10ml, and now (reaction 1) has generated 8 volumes of CO2, then there is CO2, 2ml

Case 1: CO2, 2ml

o2，4ml

c0，12ml。Friend.

Option B case 2: CO2, 2 ml

co:8ml

o2,8ml

The volume ratio is: 4:1:4

So choose B for this question

(1) If there is excess CO, it can be calculated that oxygen is 4ml, and carbon dioxide is 8ml, but there is only 2ml of carbon dioxide, and CO is 12ml. The ratio of the HU and NA is:

2) Excess oxygen, CO is 8ml, carbon dioxide is 8ml, the original 2ml of carbon dioxide, oxygen is 8ml. The scale is: 4: