What is the law of negation of negation in traditional Chinese philosophy

The main contents are as follows: "the law of affirmation and negation", one of the basic laws of materialist dialectics. The development of things is realized through his own dialectical negation

Are the plural prototypes of nouns in all English words changing

No. for example, the plural of sheep is itself

Given the triangle ABC, if ACOS a = bcos B, then the triangle is

acosA=bcosB
According to the sine theorem
a=2RsinA,b=2RsinB
Ψ 2sinacosa = 2sinbcosb (about R)
∴sin2A=sin2B
∵ a, B are the internal angles of the triangle
2 a = 2 B or 2 A + 2 b = 180;
A = B or a + B = 90 & # 186;
A triangle is an isosceles triangle or a right triangle

When are two nouns together and the former is the attributive of the latter?

This is the usage of nouns as attributives, indicating the use, material, function, category or time of things
A student teacher
A student's teacher
In most cases, nouns as attributives are usually singular
Banana trees
Newspaperboy
Country lanes
When some nouns are used as attributives, they should be consistent with the central word in number
Man cook (men cooks)
Woman teacher (women teachers)
When some nouns are used as attributives, they can only be plural
Sales man
Sales Department
Goods train
Services desk
Sports jacket
Glasses frame
Savings bank
Compound nouns with hyphens can only be used as attributives in the singular form
Three leg table
Thirty page report
Four week course
Five mile trip
One dollar book
Three act play
Attention to noun as attributive
When nouns are used as attributives directly, they are usually singular
A ticket office
Traffic lights village people
2. When the nouns sports and clothes are used as attributives, they are still in the plural
A sports field a clothes shop
3. When man and woman are used as attributives, they can be singular or plural, depending on the number of nouns they modify
A man doctor
Two women teachers
4. When some countable or uncountable nouns ending with - ICs or - s are used as attributives, they are still in the original form with the same suffix
A physics teacher a news reporter
5. When numerals and unit nouns are used as attributives together, unit nouns are often singular, and numerals and unit nouns are connected by "-"
A fourteen year old boy
A two-hour plan
A three foot high desk
6. Plural is often used as attributive in the title of unit name, newspaper, radio, TV, etc
The boys club
Learning skills center
7. The meaning of noun as attribute is different from that of noun possessive
The girl friend

It is known that D, e and F are respectively the midpoint of △ ABC

It is proved that connecting De, DF, ∵ D and F are the middle points of BC and AC respectively, ∥ DF ∥ AB, similarly, de ∥ AC ∥ quadrilateral AEDF is parallelogram, ad and EF are equally divided

The greatest common divisor of two numbers is 1 and the least common multiple is 437. These two numbers are () and () or () and ()

The greatest common divisor indicates that there is no common factor except 1 between the two numbers
And 437 = 19 * 23
So these two numbers are 19 and 23 or 1 and 437

Triangle ABC sinc = 3 / 5 CoSb = 12 / 13 find cosa find triangle shape

Cosa = - cos (B + C) = sinbsinc cosbcosc = 5 / 13.3 / 5-12 / 13. (± 4 / 5) = - 33 / 65 or 63 / 66
It's not a special triangle (isosceles or right angles), either obtuse or acute

Who are the odd and prime numbers within 20? Who are the even and composite numbers within 20? Who are the even and prime numbers?

Numbers that are both odd and prime numbers within 20 are 3, 5, 7, 11, 13, 17 and 19
The numbers that are both even and composite numbers within 20 are 4, 6, 8, 10, 12, 14, 16, 18 and 20
The number within 20 is both an even number and a prime number. It's 2. It's absolutely right. Let's share it

How to prove this formula? If two straight lines Y1 = K1X + B1 ⊥ y2 = k2x + B2, then K1 × K2 = - 1
How to prove this formula?!
If two straight lines Y1 = K1X + B1 ⊥ y2 = k2x + B2, then K1 × K2 = - 1
What's the relationship between B1 and B2?
To 1st floor: I haven't learned the formula of the angle between straight lines. Well, I'm a sophomore in junior high school. Can I use the proof that I can understand at this level? Thank you

Because Y1 = K1X + B1 ⊥ y2 = k2x + B2
So Y1 = K1X ⊥ y2 = k2x
Make any straight line perpendicular to the horizontal axis, intersection Y1 = K1X and y2 = k2x at a (x, A1), B (x, A2), perpendicular to C (x, 0)
AOC is similar to OBC
So Ca / OC = OC / BC = 1 / (BC / OC)
|k1|=|1/k2|
If K1 > 0
Then K2

Change the following sentences into plural
there is a pen in the desk.
there are sime in the desk.
look at that dog.ly 's lovely.
look at those they are lovely.
there is an apple in the basket.
there are some in the .
there is tomato near the photo.
there are some near the .
i have a wish.
i have some .

There is a pen in the desk desk.Look at that dog.lt Look at that dogs.They 're lovely.There There are some apples in the basket

What is the law of negation of negation in traditional Chinese philosophy