The answers to one variable inequality exercises in the second volume of junior high school mathematics

1. A factory wants to recruit 150 workers of a and B, whose monthly salary is 600 yuan and 1000 yuan respectively. Now the number of workers of B is not less than twice of that of a, so how many workers of a can make the monthly salary at least? 2. Linear function Y1 = 3x + 3 and y2 = - 2x + 8

If it's 12 o'clock Beijing time, how many degrees did the minute hand rotate at 12:30? How many degrees did the hour hand rotate? How many degrees did the minute hand rotate at 12:45? What about the hour hand? What's the angle between the hour hand and the minute hand?

At 12:30, the minute hand turned 180 degrees and the hour hand turned 15 degrees
At 12:45, the minute hand rotated 270 degrees, the hour hand 22.5 degrees, and the included angle 247.5 degrees

Two times T seconds equals three thirds of two times t plus two seconds

X - two fifths, x = two fifths, what is the equation? Who can tell me how to calculate it,

x-(2/5)x=2/5
(1-2/5)x=2/5
(3/5)x=2/5
x=2/5*(5/3)
x=2/3

Mathematics of senior one, known quadratic function f (x) = ax ^ 2 + BX + 4
Given quadratic function f (x) = ax ^ 2 + BX + 4, set a = {x | f (x) = x}
If a = {1}, find f (x)
Why is it that [ax ^ 2 + (B-1) x + 4 = 0 from a = {1} has two equal roots of 1]?
I mean, why is it [ax ^ 2 + (B-1) x + 4 = 0] instead of [ax ^ 2 + BX + 4 = 0]

Because f (x) = x has only one solution of 1, so f (x) - x = 0 has only one solution of 1, that is, ax ^ 2 + (B-1) x + 4 = 0 has two equal roots of 1

How to simplify the two questions of 23 times 39:14 + 14 times 39:16 and 25 times 43:37 + 37 times 43:18?
How to simplify the two questions of 23 times 39:14 + 14 times 39:16 and 25 times 43:37 + 37 times 43:18?

23 by 14 out of 39 + 14 by 16 out of 39
=14/39*(23+16)
=14/39*39
=14
25 by 37 / 43 + 37 by 18 / 43
=37/43(25+18)
=37/43*43
=37

What is the left and right limit of the discontinuous point 0-1 of the function f (x) = (x ^ 3-x) / sin π x? How to find it? Why not equate the following sin to NX?
What is the left and right limit of the discontinuous point 0-1 of the function f (x) = (x ^ 3-x) / sin π X and how to find it?

When x = 0, the limiting denominator is π X and the molecule is x (x2-1)
It is equal to - 1 / π after about X
When x equals 1, this is the post molecule equals x (x + 1) (x-1) equals 2 (x-1)
The denominator is sin π x, and then you let t = X-1, and the limit is - 2 / π
X = - 1 is the same
Sin π x can be equivalent only when x tends to 0, infinitesimal becomes π x, but not when x tends to 1!

Solving the equation of 3x-3 + 6

3x-3-6=0

Turn the following into the simplest integer ratio 5 / 8:0.759/111:1

5/8 :0.75
= 5/8 :3/4
= (8×5/8) :(8×3/4)
= 5 :6
9/111 :1
= 9 :111
= (9÷3) :(111÷3)
= 3 :37

Find LIM (n →∞) [(1 ^ 3 + 4 ^ 3 + 7 ^ 3 +...) +(3n-2)^3]/{[1+4+7+…… +(3n-2)]^2}

I'm sure the answer is 3

The answers to one variable inequality exercises in the second volume of junior high school mathematics