What is the English abbreviation of Britain and China And the United States, Canada

What is the English abbreviation of Britain and China And the United States, Canada

Eng u.k.uk the U.K
China cn
USA US u.s.a.u.s.u-s
Canada, Canada

What is the abbreviation of month?

In general, it is the first three letters, and only September is four. The details are as follows: January Jan February February Feb March Mar April APR may may may do not need abbreviation June Jun July Jul August Aug September September September September October Oct

What day is sta? Send the abbreviations of each week

Abbreviation (English week, month, etc.) week
Monday: mon
Tuesdays: Tuesdays
Wednesday: wed. = Wednesday
Thur. = Thurday
Friday: fri. = Friday
Saturday: Sat. = Saturday
Sunday: sun

Given the absolute value of a = 20, the absolute value of B = 9, and a > b, find the values of a and B (find the specific solution process)

From the number axis, a is greater than B, so a is on the right side of B
When a and B are both less than 0, it is not true
When a and B are greater than 0, a = 20 and B = 9
When a is greater than 0 and B is less than 0, a = 20 and B = - 9

F (x) is an odd function. When x belongs to (- 1,0), f (x) = LG (x + 1), then the analytic expression of F (x) in (0,1) is?

Let x belong to (0,1),
f(-x)=lg(-x+1)
Because it's an odd function, so
F (x) = - (LG (- x + 1), where x belongs to (0,1)

It is known that the function f (x) = ax + B / 1 + X2 is an odd function defined in (- 1,1)
And f (1 / 2) = 2 / 5. (1) find the expression of F (x). (2) prove by definition that the function f (x) is an increasing function in the interval (- 1,1)

(1) F (x) = (AX + b) / (1 + x ^ 2) is an odd function,
(-ax+b)/[1+(-x)^2]=-(ax+b)/(1+x^2),
-ax+b=-ax-b,
b=0.
f(1/2)=2/5,
[a*(1/2)]/[1+(1/2)^2]=2/5,
a=1.
f(x)=x/(1+x^2).
(2) . set - 1

A number is added, subtracted and divided by itself. The result of their sum, difference and quotient is 18.8. What's the number?

8.9

The function f (x) whose domain is r satisfies f (f (x) - xsquare + x) = f (x) - xsquare + X
1. If f (2) = 3, find f (1); if f (0) = a, find f (a)
2. If there is only one real number m such that f (m) = m, find the analytic expression of function f (x)

Let x = 2 and f (1) = 1
Let x = 0, then f (a) = a

It is known that the corresponding numbers of two points a and B on the number axis are - 1 and 3 respectively, and the corresponding number of the moving point P on the number axis is x (1). Whether there is a point P on the number axis, so that P goes to a and B
The sum of the distances is 5? If it exists, find the value of X. if it does not exist, explain the reason:

Exist, x = - 1.5 or 3.5

If ABC is not equal to 0, try to prove the equation AX ^ 2 + BX + C / 4 = 0, BX ^ 2 + CX + A / 4 = 0, CX ^ 2 + a
Given that ABC is not equal to 0, try to prove that the equation AX ^ 2 + BX + C = 0, BX ^ 2 + CX + a = 0, CX ^ 2 + ax + B = 0 has at least one real root

There are no real roots
Discriminant 1 = b * b-ac
Discriminant 2 = C * c-ab
Discriminant 3 = a * a-bc
Add = (a * a + b * B + C * c) - (AB + BC + AC)
=1 / 2 ((a-b) + (B-C) + (A-C) > = 0