If the real numbers x and y satisfy x + y + 1 ≤ 0 and X ≥ 0, then the value range of Y / (x-1)

If the real numbers x and y satisfy x + y + 1 ≤ 0 and X ≥ 0, then the value range of Y / (x-1)

Do a function line, get & nbsp; y = - X-1, the picture does not seem to pass up + qq984294870 & nbsp; the final result is - 1 & lt; = Y / (x-1) & lt; 0
How to arrange the ascending power of X & sup3; - 5xy & sup2; - 7Y & sup3; + 8x & sup2; y? 4A & sup2; B + 3AB & sup2; - 2b & sup3; + A & sup3; is the third after descending power
Complete answer plus reward!
What is the third term after power reduction of 4A & sup2; B + 3AB & sup2; - 2b & sup3; + A & sup3?
It depends on what you reduce the power of X: X & sup3; + 8x & sup2; y-5xy & sup2; - 7Y & sup3; y reduce the power of - 7Y & sup3; - 5xy & sup2; + 8x & sup2; y + X & sup3;
The third term reduced by a is 3AB & sup2; and the third term reduced by B is 4A & sup2; B
Solve the system of inequalities 4x + 2 ＞ 8 (x-1). 4x + 20 ＜ 8x
（1）4x+2＞8（x-1)
4x+2＞8x-8
4x-8x＞-8-2
-4x＞-10
X < 10 / 4
（2）4x-8x＜-20
-4x＜-20
x＞5
4x+2>8x-8 204x 208x-8
4x-8x>-8-2
-4x>-10
x4x.x20.x>5.
So there is no solution
A problem of quadratic equation with one variable in Junior Three
Please help me figure it out
When a container is filled with 20 kg pure alcohol, pour out part of the alcohol, pour out the same amount of solution for the second time, and then fill it with water. At this time, the pure alcohol in the container is only one fourth of the original. How many kg of solution is poured out each time? (let the density of alcohol be equal to the density of water)
I don't know if I understand correctly
Let x% be inverted for the first time
20*(1-x)(1-X)=20*(1/4)
The solution is: x = 1 / 2
So, for the first time, 20 * (1 / 2) = 10
If the real number x, y satisfies y
Y
Y
3ab+4a^2b
If the integer solutions of the inequality system 5x-a ≤ 0,6x-b > 0 are 2,3,4, then the number of different integer pairs (a, b) is 2
5x-a ≤ 0, then x ≤ A / 56x-b > 0, then x > b / 6, so B / 6 < x ≤ A / 5, because the integer solution is 2,3,4, so we know that 1 ≤ B / 6 < 2,4 ≤ A / 5 < 5, so 6 ≤ B < 12,20 ≤ a < 25, so a can take five values of 20,21,22,23,24, and B can take six values of 6,7,8,9,10,11, so different integers
20≤a
Application of quadratic equation of one variable
There are 650 pages in a book. After reading it for one day, someone stops reading it for four days because of business trip. In order to return it to the library at the specified time, he has to read 25 more pages every day. How many pages did he plan to read every day?
Let's look at page x every day
(650-x)/x-(650-x)/(x+25)=4
Through the next points out
4x^2+100x=25*650-25x
4x^2+125x-25*650=0
x=50
Let (650 / x) - 4 = (650-x) / (x + 25) be equal to 50
I planned to read x pages every day
According to the meaning of the title
x+（650÷x-5）（x+25）=650
Simplify
4x^2+125x-650×25=0
（x-50）（4x+325）=0
X = 50 (rounding off negative value)
The original plan is to read 50 pages a day.
Given that the real numbers x and y satisfy the equation x + 2Y = 6, when 1 ≤ x ≤ 3, the value range of Y − 1 x − 2 is obtained
According to the meaning of the question, draw a graph, as shown in the figure; ∵ y − 1x − 2 is the slope value of the line connecting a moving point of line AB on the line x + 2Y = 6 and point C (2,1); ∵ a (1,52), B (3,32), ∵ the slope of line BC is KBC = 1 − 322 − 3 = 12, the slope of line AC is KC = 1 − 522 − 1 = - 32, ∵ y − 1x − 2 ≥ 12, or Y − 1x − 2 ≤ - 32; ∵ when 1 ≤ x ≤ 3, the value of y − 1x − 2 The range is (- ∞, - 32] ∪ [12, + ∞)
The ascending order of polynomial 5A & sup2; b-4a & sup3; B + A + 1 according to a is as follows:
5a²b-4a³b+a+1
=1+a+5a²b-4a³b