If the solution set of x-a ≥ 1 2x + B < 2 is 0 ≤ x < 1, then the value of A-B is

If the solution set of x-a ≥ 1 2x + B < 2 is 0 ≤ x < 1, then the value of A-B is

2 / 2 x-a ≥ 1 gives x ≥ a + 1
2X + B < 2 solves X
Solution; X / 2-A ≥ 1
x≥2a+2
2x+b＜2
x＜(2-b)/2
Because 0 ≤ x < 1
So 2A + 2 = 0, (2-B) / 2 = 1
So a = - 2, B = 0
So A-B = - 2
One hundred and twenty-three
If the solution set of inequality system (x-a) / 2 ≥ 1; 2x + B < 2 is 0 ≤ x < 1, then the value of A-B is
From (x-a) / 2 ≥ 1 we get x-a ≥ 2, so x ≥ 2 + A; from 2x + B < 2 we get X
There are also the range of 3x + 5 / X and the range of 2x / (the square of 3x + 1) to find the square of x-x under the root sign
The denominator of x-x is greater than or equal to 2 times root 3
So the fraction is less than or equal to the root 3 of 3
Similarly, X
Xiao Ming wants to calculate the value of 2 ^ m% 2 ^ n and input it into the computer room. He wrongly typed the power of 2 to more than 20 and proceeded according to the wrong way
Since the quotient is greater than 1.3, and taking 21 * 1.3 is equal to 27.3, we can see that there are not many M and N in line with the meaning of the question, so we can substitute them into the data test. There are three groups
n=1,m=8; n=1,m=9; n=2,m=9
Problem solving ideas are basically like this, there is no formula ~ if you are satisfied, give a good comment, ha ha, hope to help you!
The range of function y = (x ^ 2-1) / (x ^ 2-4x + 3) is?
If the domain X & # 178; - 4x + 3 ≠ 0, then x ≠ 1, X ≠ 3
y=(x^2-1)/(x^2-4x+3)=【（x-1）（x+1）】/【（x-1）（x-3）】=(x+1)/(x-3)=1+4/(x-3)
When x = 1, y = - 1
So the range (negative infinity, - 1) ∪ - 1,1) ∪ (1, positive infinity)
First of all, the definition field of the function is obtained. From x ^ 2-4x + 3 ≠ 0, it can be concluded that x ≠ 1, X ≠ 3
The reduced function relation y = (x ^ 2-1) / (x ^ 2-4x + 3) = (x + 1) (x-1) / [(x-1) (x-3)] = (x + 1) / (x-3) = 1 + 4 / (x-3)
Discussion by domain
1. When x
Xiao Ming divided a number by 2 / 3 and miscalculated it by 2 / 3. The result is 2.4. The correct answer is ()
Original number: 2.4 △ 2 / 3 = 3.6
The correct answer is: 3.6 △ 2 / 3 = 5.4
x*2/3=2.4
x=3.6
x÷2/3=3.6÷2/3=5.4
The correct answer is (5.4).
Five point four
2.4/(2/3)/(2/3)=5.4
Xiao Ming divided a number by 2 / 3 and miscalculated it by 2 / 3. The result is 2.4. The correct answer is (5.4).
The range of function y = 5 - √ (- x ^ 2 + 4x + 21) (- 2 ≤ x ≤ 5) is
y=5-√(-x^2+4x+21)
y=5-√(-4-x^2+4x+25)
y=5-√25-(x-2)^2
Zero
What is the single digit of the result of the 2011 power of 2 minus 1?
The first power of 2 = 2, the second power of 2 = 4, the third power of 2 = 8, the fourth power of 2 = 16, the fifth power of 2 = 32 (the number of digits is the same as the first power of 2, repeated every four times)
2011 = 502 * 4 + 3, so the 2011 power of 2 is the same as the 3rd power of 2, that is 8,8-1 = 7
So the 2011 power of 2 minus 1, the single digit of the result is 7
X ∈ (1,4), then the range of function y = - x ^ 2 + 4x + 5 is
y=-(x-2)^2+9
The axis of symmetry is x = 2 and the opening is downward
The maximum value is y (2) = 9
On (1,4), 4 is larger than 1 from the symmetry axis X = 2, so the minimum value is y (4) = 5
So the range is (5,9]
The 2011 power of 3 plus the single digit of 1
The first power of 1 = 3
The second power of 3 = 9
The third power of 3 = 27
The fourth power of 3 = 81
The fifth power of 3 = 243
So it's a cycle of 3 to the fourth power
2011÷4=502…… Three
The 2011 power of 3 plus 1 is 7 + 1 = 8
The 2011 power of 3 plus 1 has a single digit of 8
The single digit is 8
=502 power of [4 power of 3] + 1
=[502 power of 81] x27 + 1
The last position of [502 power of 81] is 1
Ten thousand words are omitted below
For example, we don't understand the process of √ 4x2 + 4x2 +
Dial: the original function deformation, construction of plane graphics, geometric knowledge, determine the function value
The deformation of the original function is f (x) = √ (x + 2) 2 + 1 + √ (2-x) 2 + 22
Make a rectangle ABCD with length of 4 and width of 3, and then cut it into 12 units
Let HK = x, then EK = 2-x, KF = 2 + X, AK = √ (2-x) 2 + 22,
KC=√(x+2)2+1 .
From the triangle trilateral relation, AK + KC ≥ AC = 5
Take the equal sign when the line is closed
The domain of the original function is {y | y ≥ 5}
f(x)=√[(x+2)^2+1]+√[(x-2)^2+4]
It can be regarded as the sum of the distances from the point (x, 0) on the X axis to the other two points a (- 2,1) and B (2,2),
According to the principle of image, the x-axis image point B '(2, - 2) of B (2,2) is made. The minimum distance point is the intersection (- 2 / 3,0) of the line ab' and the x-axis
Length with minimum distance ab '= 5
So Y > = 5, when x = - 2 / 3, take the minimum value