Logarithmic function (7 17:48:51) Given that the range of y = ㏒ 0.5 (x2-2x + a) is r, the value range of a is obtained

Logarithmic function (7 17:48:51) Given that the range of y = ㏒ 0.5 (x2-2x + a) is r, the value range of a is obtained

The range is r, that is, the range of x ^ 2 - 2x + a includes all positive numbers
So the minimum is A-1

Trigonometric function (20 17:30:51)
If Cos2 α / sin (α - π / 4) = - (radical 2) / 2 & # 160; then sin α + cos α=

[cos2a] / sin(a-π/4)=-√2/2
[cos2a] / sin(a-π/4)
=（cosa-sina)(cosa+sina)/[√2(sina-cosa)/2]
=-(cosa+sina)/(√2/2)
=-√2/2
So Sina + cosa = 1 / 2

Set (11 21:21:51)
Let a = {x | 2A + 1 ≤ x ≤ 3a-5}, B = {x | y = √ (3-x) (x-22)}, then a sufficient and unnecessary condition for a to belong to (a ∩ b) is

The nonempty set a = {x|2a + 1 ≤ x ≤ 3a-5}, so it satisfies 2A + 1 = 6;
B={x|y=√(3-x)(x-22)}={x|3

Ln (a + x) derivation

One of (a + x)

Calculation of 4538 + 3998 3.2 × 10.1 38 × 99 + 38 7 / 15 △ 5 + 8 / 15 × 1 / 5 1-0.225 △ 0.9-0.75 65 × 65 / 66 by simple method
2.5×3.2×12.5

4538+3998
=4538+4000-2
=8538-2
=8536
3.2×10.1
=3.2×10+3.2×0.1
=32+0.32
=32.32
38×99+38
=38×（1+99）
=38×100
=3800
7/15÷5+8/15×1/5
=（7/15+8/15）×1/5
=1/5
1-0.225÷0.9-0.75
1-（0.25+0.75）
=1-1
=0
65×65/66
=65×（1-1/66）
=65-65/66
=64 and 1 / 66
2.5×3.2×12.5
=2.5×4×（0.8×12.5）
=10×10
=100

Help me!
Simplification ratio: 36:720.28:0.49 three fifths: four fifths: 0.75
The ratio of the following ratios: 150:30.3:0.75 5 / 7: 3 / 8 0.125: 3 / 8 12:36 4 / 5: 8 / 35
Please help me!

Question 1: 1:2 4:7 9:4 1:6 1:150 1:1
Question 2: 500.4 1.905 (40 / 21) 0.333 (1 / 3) 0.333 (1 / 3) 3.5

Given that the function g (x) = - x2-3, f (x) is a quadratic function, when x ∈ [- 1,2], the minimum value of F (x) is 1, and f (x) + G (x) is an odd function, the analytic expression of F (x) is obtained

Let f (x) = AX2 + BX + C (a ≠ 0), then f (x) + G (x) = (A-1) x2 + BX + C-3, ∵ f (x) + G (x) is an odd function, ∵ a = 1, C = 3 ∵ f (x) = x2 + BX + 3, symmetry axis X = - B2, when - B2 > 2, that is, B < - 4, f (x) is a decreasing function on [- 1, 2], and the minimum value of ∵ f (x) is f (2

Can 6.5 × 101-65 × 0.1 be simplified? If so, how?

Original formula = (6.5 * 10) * (101 / 10) - 65 * 0.1
=65*10.1-65*0.1
=65*(10.1-0.1)
=65*10
=650

LIM (when x tends to 0) [(e ^ x + e ^ 2x + e ^ 3x +...) What is the limit of e ^ NX) / N] ^ (E / x), where n is a given positive integer
Use the lobita rule

1 equation (A-1) x2 + ax + 1 = 0 is a one variable linear equation about X, then a=__________________
It takes 8 days for team a to complete a project alone, and 9 days for team B to complete it alone. Now team a will do it alone for 3 days, and then team B will support it. Team B will complete 3 / 4 of the task together after X days. Therefore, the equation is as follows_______________
3. For a two digit number, the sum of one digit number and ten digit number is 9. If the new number obtained by the transposition of one digit number and ten digit number is 9 larger than the original number, let the one digit number be x, then the equation can be formulated as____________________________
4 given that x = - 3 is the solution of the equation 3 [x + 4] - 4-2a = 1 about X, find the value of A-1 / A.
For a project, it takes 10 days for Party A to complete it alone, 12 days for Party B to complete it alone, and 15 days for Party C to complete it alone. After three days of joint work, Party A leaves because of something, and Party B and Party C continue to work together. How many days will it take to complete it?
Solution: the design will take X days to complete
According to the meaning of the title, the equation is as follows______________________________
The results are as follows_________________
After examination, it is consistent with the meaning of the question
A: we still need to_________ Genius can do it
The nonnegative integer solution of the bivariate linear equation x + 3Y = 7 is__________ .
7. Party A and Party B process a batch of parts at the same time. In the first three hours, they process a total of 126 pieces. In the last five hours, party a first spends an hour repairing tools. Therefore, Party A processes 10 pieces more per hour than before. As a result, in the later period, Party A processes 10 pieces more than Party B. how many pieces did Party A and Party B process each hour?
It's a process

1 equation (A-1) x2 + ax + 1 = 0 is a one variable linear equation about X, then a=_________ Arbitrary real number_______ It takes 8 days for team a to finish a project alone, and 9 days for team B to finish it alone. Now team a will do it alone for 3 days, and then team B will support it. Team B will finish 3 / 4 of the task after X days