It shows that the square difference of two adjacent positive integers is odd

Let two adjacent numbers be 2n, 2n + 1 respectively
(2n + 1) ^ 2 - (2n) ^ 2 = 4N + 1 is odd
Let two adjacent numbers be 2N-1 and 2N-1 respectively
(2n) ^ 2 - (2n-1) ^ 2 = 4N-1 is odd
So it must be odd

Using degrees, minutes and seconds to express 32.26 ° need to answer the process

0.26×60=15.6
0.6×60=36
So it's 32 ° 15'36 ″

When using scissors to cut thick paper, the tip of the scissors is not easy to cut, but the middle of the scissors is easy to cut
A. The drag B is reduced, the power C is increased, the drag arm D is reduced and the power arm is increased

Power x power arm = resistance x resistance arm
The power arm is invariable, easy to cut is not only the power is reduced, so either the resistance is reduced or the resistance arm is reduced, and the resistance is the friction between scissors and paper, which is also invariable, so the resistance arm should be reduced

Fold a rope 50 times and cut it from the middle. How many pieces has the rope been cut into?

Answer: 2 to the 50th power plus 1
This question was said by teacher Orsay,
In fact, the most simple and intuitive method is drawing
Just draw a line on the paper
After folding for the first time, draw a line ">" similar to the greater than sign. At this time, if you cut it, it will be 3 segments
Draw a picture of the second fold, similar to "m" across, at this time if cut, it is 5 segments
Fold it for the third time, which is similar to joining "mm" horizontally. At this time, if you cut it, it is 9 segments
...
Analysis:
The first fold and cut: 3 segments are the power of 2 plus 1
The second fold and cut: 5 segments are the second power of 2 plus 1
The third fold and cut: 9 is the third power of 2 plus 1
and so on,
The 50th fold and cut: both: the 50th power of 2 plus 1
It's easy to solve and it won't waste your time,
My friend, you are easy to learn. I admire you

How many pieces of a rope are cut by folding it in half, folding it in half, and then cutting it from the middle?
It's OK to solve the equation as well as the formula

Cut into 5 sections
One rope is folded in half, and then folded in half. That is four strands. If you cut it from the middle, it should be eight segments. But if there are three ends connected, three segments will be reduced
Therefore, there are: 1 * 2 * 2 * 2-3 = 5 sections

Hairdresser's scissors, tailor's cloth knife and gardener's branch knife are labor-saving

If we put aside the weight of the scissors, the gardener's knife is the most labor-saving, because the handle is long enough to do the same work with the least effort

How to use the same scissors to cut paper
Refers to the tip of the scissors or use the back of the paper-cut more labor-saving, ha ha. Lever principle in Physics

Using the tail of the scissors, the moment is large and the force saved is small~

Children like paper-cut, but just random cut or draw some simple graphics cut out, how to let him use scissors correctly

With the child's mind, let the child free paper-cut, do not have to do too much guidance, you can choose some of these books for children to see, to ensure that children can use scissors safely

Why is it easier to cut objects with the inner end of the scissors than with the tip

According to the lever principle, with the rotation axis of the scissors as the center, the closer to the inner end, the shorter the force arm. From the formula, we can know that the closer to the inner end, the greater the force on the object, so it is easier to cut the object!

Do many people use scissors to cut paper

Experts are scissors. Carving focuses on design, not a map

It shows that the square difference of two adjacent positive integers is odd