Open cubic root of many numbers Baidu knows that in the popularization of knowledge, 188132517 is cubic. Why can 188 decide that the first number is 5?

Open cubic root of many numbers Baidu knows that in the popularization of knowledge, 188132517 is cubic. Why can 188 decide that the first number is 5?

∵ 5 ^ 3 = 125188 ∵ 188 the first digit of the open cube is 5

-What is the cubic root of 1

-The cubic root of 1 is - 1, - 1 / 2 + √ 3I / 2, - 1 / 2 - √ 3I / 2

How to open cube root

The first method is to divide the integral part of the number to be opened into three groups from one digit to the left. The second method is to find the highest number of cubic root according to the leftmost group. The third method is to subtract the cube with the highest number of cubic root from the first group and write the second group number on the right. The fourth method is to find the square of the highest number of cubic root

It is known that A. B is a rational number, m and N represent the integral part and the fractional part of 5-genhao7 respectively, and amn + B is multiplied by the square of n = 1, and 2A + B =?

2＜√7＜3
The integral part of 5 - √ 7 is 2
The decimal part is 3 - √ 7
2(3-√7)a+b(3-√7)²=1
That is, 2 (3 - √ 7) a + B (16-6 √ 7) = 1
That is, 6a + 16b-2 √ 7a-6 √ 7b = 1
We get 6A + 16b = 1
2√7a-6√7b=0
We can get a = 3B
18B + 16b = 1, that is, B = 1 / 34, a = 3 / 34
2a+b=2*3/34+1/34=7/34

The passenger car and the freight car leave from a and B at the same time. The passenger car travels 60km per hour, and the freight car travels 1 / 15 of the whole journey per hour. When they meet, the distance the passenger car travels is the freight car
5 / 4 of the car, how many km is the distance between a and B?

When they meet, the distance of the bus is 5 / 4 of that of the truck
Truck speed: 60 △ 5 / 4 = 48 km / h
Total length: 48 △ 1 / 15 = 720km

Using the collocation method to solve the equation 20m & # 178; X & # 178; + 11mnx-3n & # 178; = 0

From 20m to 178; X to 178; + 11mnx-3n to 178; = 0
x²+11nx/20m-3n²/20m²=0
x²+11nx/20m+121n²/1600m²=3n²/20m²+121n²/1600m²
（x+11n/40m)²=361n²/1600m²
①x+11n/40m=19n/40m
That is x = n / 5m
②x+11n/40m=-19n/40m
That is x = - 3N / 4m

How many kilometers per hour can cheetah reach

Cheetah's top speed can reach 110 kilometers per hour. But it can't last 15 seconds. So it's called the champion of sprint. In Africa, the second is the takin. Its speed can also reach 890 kilometers

How to solve the equation with two unknowns?

The solution of binary equations?
There should be two equations with unknowns,
Let's first express one unknown with another,
Then it is substituted into the second equation to solve the value of the second unknown, and then it is brought into any equation to solve the value of the first unknown

It takes about several hours for a spaceship that can fly 8 kilometers per second to fly from the earth to the moon

The distance from the earth to the moon is 384000 km
384000 / 8 = 48000 seconds = 13.3 hours

4X minus seven fifteen equals seven fifteen

4X - 7/15 = 7/15
4X = 14/15
X = 7/30