Irregular plural table For example, we need a simple list of common irregular plural nouns. The best form is table

Irregular plural table For example, we need a simple list of common irregular plural nouns. The best form is table

The irregular change of plural noun 1) child --- children foot --- feet --- teathmouse --- Mie man --- men woman --- women. Note: the plural forms of compound words with man and woman are also - men and - women
How to distinguish the singular and plural of English nouns
Generally, countable nouns can be divided into singular and plural
To distinguish, we must first observe
The plural of a noun is changed from the singular. The general rule is as follows
Such as: 1. Directly add s, the most common apple singular - apples complex
2. The ending is ch, SH, x, s, O (living), plus es
For example: watch singular -- watches (plural) dish -- dishes (plural) box -- boxes (plural)
There are some other situations that we will not list
So when you see that some nouns end with s, they are plural
In addition, there are some nouns with the same singular and plural
For example: people, sheet, etc
There are also some irregular changes, the plural of child mice
Remember these special things
If necessary, I can call you
Most words are plural nouns, followed by s: tables --- > tables, apple --- > apples
A small number of words, nouns, singular and plural, do not add S. these special changes should be memorized one by one: man --- > men, datum --- > data.
English words ending with F, when plural, you can change f into ves or add s directly
There are not many plural nouns ending with f or Fe, so they can be summarized into the following three types. Basically, you can recite them. There are no rules to find, so it depends on your memory. These include the usages you need in daily life
Given the function f (x) = 1 / 3x ^ 3-2x ^ 2 + ax (a belongs to R), there is and only one tangent of the curve f (x) which is perpendicular to the straight line y = X. let the inclination angle of the tangent at any point of the curve y = f (x) be α, and find the value range of α
tanα=f'(x)=x^2-4x+a=(x-2)^2+a-4
This function is a parabolic function with the opening upward, and only when x = 2 has the minimum value A-4
When x ≠ 2, the corresponding f '(x) is the same in two places,
That is, except for x = 2, there is a corresponding position in every other place, and the tangent slope is the same
According to the meaning of the title
a-4=-1
A=3
f'(x)min=-1
tanα>=-1
Zero
There is an integer that is added, subtracted, multiplied, and divided by itself. The sum, difference, product, and quotient of the sum, difference, product, and quotient are equal to 81. What is the integer?
Note: please use the elementary method to solve, not quadratic equation
Subtract 0, divide 1
81-1 = 80, now calculate the integer below 9 times yourself:
Because 80 = 64 + 16
This integer is 8
It is known that f (x) is an odd function and when x < 0, f (x) = the square of X + 3x + 2. If n ≤ f (x) ≥ m is constant when x ∈ [1,3], then the minimum of m-n
It is known that f (x) is an odd function and when x < 0, f (x) = the square of X + 3x + 2. If n ≤ f (x) ≥ m holds when x ∈ [1,3], what is the minimum value of M-N?
A.2 B.9/4 C.3/4 D.1/4
When x is less than 0, f (x) = the square of X + 3x + 2, and the odd function is f (x) = - f (- x), so when x is greater than 0, f (x) = - (the square of x-3x + 2) = - the square of X + 3x-2 formula F (x) = - (the square of x-1.5) + 0.25, because x ∈ [1,3], (draw a picture
Choose B
There is an integer that adds, subtracts, multiplies, and divides itself. The sum, difference, product, and quotient of this integer add up to 36,
The sum, difference, product and quotient of an integer added, subtracted, multiplied and divided by itself are equal to 36
5 + 5 + 5 - 5 + 5*5 + 5/5 = 36
It is known that f (x) is an odd function, and when x ＜ 0, f (x) = x2 + 3x + 2. If x ∈ [1,3], the maximum value of F (x) is m and the minimum value is n, the value of M-N is obtained
∵ when x ＜ 0, f (x) = x2 + 3x + 2, and f (x) is an odd function, so when x ＜ 0, - x ＞ 0, ∵ f (x) = - f (- x) = - [(- x) 2 + 3 (- x) + 2] = - x2 + 3x-2 = - (x − 32) 2 + 14, when x ∈ [1,3], then when x = 32, the maximum value of the function is 14, and when x = 3, the minimum value of the function is - 2, thus M = 14, n = - 2, ∵ M-N = 14 - (- 2) = 94
How to add, divide, multiply and subtract the nine numbers from 1 to 9 to make it equal to 22
Mathematical answer group for you to answer, I hope to help you
（1+2+3-4）×5+6+7+8-9 =22
（1×2×3-4）×5+6+7+8-9 =22
（1+2）×3-4+5+6+7+8-9 =22
（1+2）×3+4+5-6-7+8+9 =22
（1+2-3+4+5-6）×7-8+9 =22
（1×2×3×4+5+6）÷7+8+9 =22
wait...
It is known that y = f (x) is an even function. When x > 0, f (x) = x + 4x, and when x ∈ [- 3, - 1], n ≤ f (x) ≤ m is constant, then the minimum value of N-M is______ .
From the meaning of the question, ∵ y = f (x) is an even function, X ∈ [- 3, - 1], so consider the symmetric interval [1,3] f (x) = x + 4x, when the minimum value is x = 2, the value is 4, and f (1) = 5, f (3) = 133, so the range of F (x) on [1,3] is [4,5], so the minimum value is M-N = 5-4 = 1, so the answer is 1