The greatest common factor of two adjacent non-zero natural numbers is ()

The greatest common factor of two adjacent non-zero natural numbers is ()

Product of two numbers

The set of positive integers and negative integers is ()
A. Set of integers B. set of rational numbers C. set of natural numbers D. none of the above is true

Because the combination of positive integer set and negative integer set cannot form an integer set (integer set includes positive integer set, 0 and negative integer set), it is included by rational number set (integer set and fractional set), and natural number set contains positive integer set, but not negative integer set, so the above statements are all wrong

Find a rule: the first row has 1 cube, the second row has 3 cubes, the third row has 6 cubes, the fourth row has 10 cubes, and how many cubes does the n row have

(1+n）n/2

In order to ensure that the product of these numbers can be divided by 15, we need to find the minimum number of these 100 natural numbers from 1 to 100

I don't know if I understand right. The first number you take is not sure. That can't guarantee that the first number you take is 15, 30, 45 and so on. Among those 1 to 100, there are 14 that can be divided by 5 but not by 3. They are divided into group A, such as 5, 10, 20, 25 Can be divided by 3 but can not be divided by 5, a total of 27, divided into group B, such as

-Simplification of root sign (8 / 729)

-Root of 3 times (8 / 729)
=Root of 3 times (8 / 729)
=2/9

What/letter/should/appear/next?
When will you know the answer?

What letter / letter will appear next? The translation of letter depends on the context

The plane equation which passes through point (3,0, - 1) and is parallel to plane 3x-7y + 5z-12 = 0 is solved

Since the plane is parallel to the plane 3x-7y + 5z-12 = 0, the normal vectors of the two planes are the same, n = (3, - 7, 5), and the plane passes through the point (3, 0, - 1), so the equation of the plane is 3 (x-3) - 7 (y-0) + 5 (Z + 1) = 0, that is, 3x-7y + 5z-4 = 0

As shown in the picture, it is a rectangular square with the length of AM and the width of BM. At the four corners of the square, there is a quarter round grassland with the same radius, and the radius of the circle is RM
If the rectangle is 300m long, 200m wide and the radius of the circle is 10m, calculate the area of the square space. (π takes 3)

Area of rectangle: 300 * 200 = 60000 (m ^ 2)
Area of four quarter circles: 3 * 10 ^ 2 = 300 (m ^ 2)
The area of the square is 60000-300 = 59700 (m ^ 2)

1-20, 30.40.50.60.70.80.90
Do me a favor with these 27 numbers

1 one2 two3 three4 four5 five6 six7 seven8 eight9 nine10 ten11 eleven12 twelve13 thirteen14 fourteen15 fifteen16 sixteen17 seventeen18 eighteen19 nineteen20 twenty30 thirty32 thirty-two40 forty50 fift...

How to simplify the calculation
2800 △ 25? 6×99%+0.06、19/20×21

12/1.25=(12*8)/(1.25*8)=96/10=9.6
2800/25=(2800*4)/(25*4)=11200/100=112
6*0.99+0.06=6*(0.99+0.01)=6
19/20*21=(20-1)*(20+1)/20=(20*20-1)/20=20-1/20=20-0.05=19.95