System of inequalities {3 (x + 2) + 5 (x-4)

System of inequalities {3 (x + 2) + 5 (x-4)

From 3 (x + 2) + 5 (x-4)

If a < 0 is known, then the solution of the inequality ax < 5 about X is_______ The solution of; 5x < A is_______ .

If a < 0 is known, then the solution of the inequality ax < 5 about X is_ x>5/a______ The solution of 5x < A is u X

If a < 5 is known, then the solution set of the inequality system ax ≥ 5x + A + 1 is --

∵a＜5
∴a-5﹤0
∴X≤﹙a＋1﹚／﹙a-5﹚
The solution set of the inequality system ax ≥ 5x + A + 1 of X is x ≤ (a + 1) / (a-5)

What is the difference between the sum of the coefficients and the sum of the binomial coefficients?

Coefficients: coefficients of unknowns, which can be positive or negative
The sum of the coefficients = the coefficient of the unknown
Binomial coefficient: the combination number of unknowns, which is positive
Sum of binomial coefficients = C (n, 0) + C (n, 1) +... + C (n, n) = 2 ^ n

Given A-B = 5, ab = 3, find the value of (a + b) ^ 2 and 1 / 2 of a ^ 2 + 1 / 2 of B ^ 2

(a+b)^2
= (a-b)^2 +4ab
= 25 + 12
= 37
1/a^2 + 1/b^2
= (a^2+b^2)/(ab)^2
= [(a-b)^2+2ab]/(ab)^2
= [ 25+6]/9
= 31/9

For example, 16 times the square of (2x-1) = 25 times the square of (x-1), the factorization method of quadratic equation of one variable is used to solve the equation,

16 times the square of (2x-1) = 25 times the square of (x-1),
16 times the square of (2x-1) - 25 times the square of (x-1) = 0
[4(2x-1)+5(x-1)][4(2x-1)-5(x-1)]=0
(13x-9)(3x+1)=0
x=9/13 x=-1/3

Solve the equation, x ^ 5 + 2x ^ 4 + x ^ 3 + 2x ^ 2-6x-12 = 0

x^4(x+2)+x^2(x+2)-6(x+2)=0
(x+2)(x^4+x^2-6)=0
(x+2)(x^2+3)(x^2-2)=0
Three real roots are obtained
x=-2,±√2

There is a column of numbers A1, A2, A3. A2007 starts from the second number, and each number is equal to the difference between 1 and the reciprocal of the number in front of it. If A1 = 2, then a2007 is?
Please be as detailed as possible if you can

A1=2,A2=1-1/A1=1-1/2=1/2,A3=1-1/A2=1-2=-1,
A4=1-1/A3=2=A1,A5=1-1/A4=1-A1=1/2=A2,A6=1-1/A5=-1=A3
By analogy, we conclude that a2007 = a2004 = a2001. = A3 = - 1

14x=(75÷2-x)16

14x=(75÷2-x)16
14x=(75/2-x)*16
14x=600-16x
14x+16x=600
30x=600
x=20

The set of points on the line X-Y + 2 = 0 in the plane rectangular coordinate system

A={(x,y)|x-y+2=0,x∈R,y∈R}
In fact, as long as the set can represent the characteristics of an element, or the relationship between two elements, it is generally expressed by equations, and also pay attention to the domain of definition ~!