Chapter 2: addition and subtraction of integral, 2

Chapter 2: addition and subtraction of integral, 2

Think for yourself, I can tell you the answer, will you, think for yourself

For the inequality ax & # 178; - BX + C > 0 of X, the solution set is (- 2,1). For the coefficients a, B, C, we have the following conclusion
①a＞0
②b＞0
③c＞0
④a+b+c＞0
⑤a-b+c＞0
The number of the correct conclusion is____________
Please write the answer and the solution, thank you!

The solution set of inequality ax & # 178; - BX + C > 0 is (- 2,1),
If the coefficient of quadratic term is greater than 0, then the solution set of inequality should take two sides. Now the solution set is (- 2,1), so A0
Similarly - 1 ∈ (- 2,1) x = - 1 ax & # 178; - BX + C = a + B + C > 0
1 is the root of the equation AX & # 178; - BX + C = 0, so x = 1 ax & # 178; - BX + C = A-B + C = 0
therefore
①a＞0
②b＞0
③c＞0
④a+b+c＞0
⑤a-b+c＞0
The number of the correct conclusion is_____ 2,3,4_______

The absolute value of one number is twice the absolute value of another number, and the distance between two corresponding points on the number axis of these two numbers is 6. Try to explore these two numbers according to the following conditions
(1) The two points are on the same side of the origin
(2) These two points are on the opposite side of the origin

（1）6÷(2-1)=6
6×2=12
The two points are 6 and 12 or - 6 and - 12, respectively
（2）6÷（2+1）=2
2×2=4
The two points are 2 and - 4 or - 2 and 4, respectively

The function y = f (x) is a decreasing function on (- 1,1) and an odd function satisfying f (a2-a-1) + F (A-2) > 0. Try to find the range of A

From the topic meaning, f (a2-a-1) + F (A-2) > 0, that is, f (a2-a-1) > F (A-2), and function y = f (x) is odd, so f (a2-a-1) > F (2-A), and function y = f (x) is a decreasing function on (- 1, 1), so there is − 1 ＜ A2 − a − 1 ＜ 1 − 1 ＜ a − 2 ＜ 1A2 − a − 1 ＜ 2 − a, {1 ＜ a ＜ 0 or 1 ＜ a ＜ 21 ＜ a ＜ 3 − 3 ＜ a ＜ 3, so the value range of a is ＜ 1 ＜ a ＜ 3 The circumference is (1, 3)

2 & # 179; and 3 & # 178; are the same category. Judge right or wrong

Items with the same letter and the same index of the same letter are called similar items, such as 4Y and 5Y, 100ab and 14ab
2 & # 179; and 3 & # 178; in the final analysis, 8 and 9 are both numbers, so they are of the same kind

If the function y = x ^ 2-2ax has an inverse function in the interval (- 2,1), what is the value range of a?

That is, the function is monotone in this interval, and the axis of symmetry is not in this interval
And the axis of symmetry is x = a
So a > = 1 or a

Given the function f (x) = ln [e ^ x-e ^ (- x)], then f (x) is
Why choose a (non odd and non even function, and increase monotonically on (0, positive infinity)?
The main question is how to use e ^ x-e ^ (- x) > 0

First of all, to judge the parity depends on whether the domain is symmetrical about the origin. Only when the domain is symmetrical can we judge the parity
Domain of definition
e^x-e^(-x)>0
e^x>e^(-x)
x>-x
2x>0
x>0
The domain of definition is not symmetric about the origin, and ∧ is a non odd and non even function
This is a composite function
LNU is increasing outside
Internal u = e ^ x-e ^ (- x)
E ^ x is increasing
E ^ (- x) is minus
-E ^ (- x) is increasing
The internal u = e ^ x-e ^ (- x) is increasing
The whole function f (x) is an increasing function
Choose a

The relationship between left limit and right limit and the existence, continuity and differentiability of limit in function
Limit existence = > differentiable = > continuous left and right limits exist and are equal
What about the relationship between left and right limits and the existence of limits?

Let a be a symmetric matrix of order n and B be an antisymmetric matrix of order n. It is proved that the square of B is a symmetric matrix and ab-ba is also a symmetric matrix

B ^ 2 = (- B ^ t) (- B ^ t) = (b ^ t) ^ 2 = (b ^ 2) ^ t, which indicates that B ^ 2 is a symmetric matrix (ab-ba) ^ t = (AB) ^ t - (BA) ^ t = (b ^ t) (a ^ t) (b ^ t) = (- BA) - (- AB) = - Ba + AB, which indicates that ab-ba is also a symmetric matrix

The rules of plural change of countable nouns [1]: the plural of nouns is regular, generally adding s at the end of words; the consonant letter + Y type, changing y into I, es;
The plural change of countable nouns [1]:
The plural number of nouns is regular. Generally, s is added at the end of the word;
Consonant letter + Y type, change y to I, es;
CH, SH, s, x, es;
f. Fe is really stingy, the letter V to replace it, es after don't forget;
It's amazing that the letter O comes. There is life to es, but there is no life + s
ch

For words ending with CH, SH, s, x, add es at the end of the word,