The solution of inequality (6x-x2-x3) (x2-7x + 10) is greater than 0

The solution of inequality (6x-x2-x3) (x2-7x + 10) is greater than 0

0 less than x less than 5 or - 3 less than x less than 0
What's wrong with the decomposition upstairs?

Inequality 7x + 5-2 is greater than 2 (x + 1)

(7x+5)/7-2>2(x+1) (7x+5)-14>14(x+1) 7x+5-14>14x+14 -23>7x x

Solution inequality (6x-x-x-3) (x-7x + 10) > 0

Inequality can be reduced to (x ^ 3 + x ^ 2-6x) (x ^ 2-7x + 10)

The solution set of inequality 2-7x ≤ 4-6x is

2-7x《4-6x
-7x+6x《4-2
-x《2
x》-2

The solution set of inequality 6x's square-7x + 2 ≤ 0 is

6x^2-7x+2≤0
(2x-1)(3x-2)≤0
x1=1/2,x2=2/3
Because the coefficient of quadratic term 6x ^ 2 is 6 > 0
So the parabolic opening is upward
Therefore, the solution set of inequality is between two sets
1/2≤x≤2/3

Find the square of solution set 3x + 7x + 2 > 0 of the following inequality
This is the content of senior one. I hope someone can help me with it,
How to apply - ∞ and + ∞?

The factorization is (3x + 1) (x + 2) > 0
That is, (x + 1 / 3) (x + 2) > 0
That is X-1 / 3
So the solution set is {x | X-1 / 3}

Solve the following inequality 5 (2x-7) 4 (x + 8)
"Fast" is less than or equal to the symbol

5(2x-7)≤4(x+8)
10x-35≤4x+32
10x-4x≤35+32
6x≤67
x≤67/6

Huke edition, Chapter 7 testing (b)
17. A runs at the speed of 5km / h, and after 2h, B starts from the same place by bike and pursues a along the same road. However, the two of them agree that B should catch up with a no earlier than 1h and no later than 1.25h. Can you be sure what range should be controlled by cycling speed?
We should explain and calculate in detail,

When 1 h overtakes, the speed of B is the fastest, which is set as x1. When 1.25 h overtakes, the speed of B is the slowest, which is set as x2
X1=(2+1)*5
X1=15
1.25*X2=(1.25+2)*5
X2=13
So the range is within 13 ~ 15km

Shanghai Science Edition seventh grade mathematics basic training 1

1. Percentile: 37.6.5 percentile: 31.8.5 percentile: 32.0.0 thousand; 23.5 thousand: 21.1 ten thousand; 31.0.12.6.0483: 8.67 × 107 (7 is the power); 8.1 × 103 (3 is the power); 9.1 × 103 (3 is the power); 8.03. A D D4. Uncertainty (- 555) 2 = 3.08 × 105 (5 is the power)

Shanghai Science Edition Grade 7 Volume 2 basic mathematics training page 67,
Page 67 12 questions. Factoring and expanding space multiple choice questions are published by the times,

（A-B-2）（A-B＋1） （A＋B＋3）（A＋B-2） （a-b＋1）（A-B-1） （1＋X-Y）（1-X＋Y）