How to set up this problem

－16+12－24+18

In 4,6,8,12,16,18,20,24, which are multiples of 4

4.8.12.16.20.24 is an integral multiple
Others are non integral multiples

2,6,4,12,8,18,16,24,( )
jkuj

2,6,4,12,8,18,16,24,(32 )
Odd: 2, 4, 8, 16, (32) followed by twice the front
Even items: 6, 12, 18, 24, the difference is 6

（6+12+18+24+… +240）－（4+8+12+16+… +160）=

(6+6*2+6*3+...+6*40) - (4*1+4*2+4*3+...+4*40)=6*(1+2+3+4...+40) - 4*(1+2+3+4+...+40)=(1+2+3+4+5+...+40)*(6-4)=820*2

Xiaoqiang's 12 step walk is 9 meters, Xiaohua's 16 step walk is 13 meters. Who takes a step longer on average?

9/12=0.75 13/16=0.8125
8125 > 0.75, so the average length of Xiaohua's step is longer

Y. Divide 15 by 1, 2x, etc. divide 15 by x minus 1 by 12

15/1.2x=15/x-1/12
Multiply both sides by 12x
150=180-x
x=180-150
x=30

If y = 3 ^ (x ^ 2-2x) is known, find the subtraction interval

Using the derivative formula

x^2+4x+4/x+2÷(x^2+2x)

(x^2+4x+4)/(x+2) ÷ (x^2+2x)
= (x+2)^2/(x+2) ÷ x(x+2)
=1 ÷ x
=1/x

Y * y * y * y + 2x * x * x * x = 4x * x * y find out how much x is equal to and how much y is equal to. Write all the options!

The original equation is arranged as follows
2x^4－4x^2y＋y^4＋1＝0
Then the quadratic equation of one variable with respect to x ^ 2 has a real number solution
(－4y)^2－8(y^4＋1)≥0
That is: (y ^ 2-1) ^ 2 ≤ 0
If and only if y ^ 2-1 = 0, the above equation has real solution
So y = 1 or y = - 1
When y = 1, the original equation is changed to 2x ^ 4-4x ^ 2 + 2 = 0
The solution is: x = 1 or x = - 1
When y = - 1, the original equation is changed to 2x ^ 4 + 4x ^ 2 + 2 = 0
There is no real solution to this equation
So all pairs of real numbers are (1,1), (- 1,1)

Decompose the following factors: (1) Mn2 + 6MN + 9m; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; (2) 4x2 (a-b) + (B-A)

（1）mn2+6mn+9m，=m（n2+6n+9），=m（n+3）2；（2）4x2（a-b）+（b-a），=（a-b）（4x2-1），=（a-b）（2x+1）（2x-1）．

How to set up this problem