The new library is open. Xiao Hong goes to the library every three days and Xiao Ling goes every four days. After Xiao Hong and Xiao Ling meet in the library one day, they may meet again in the library after () days A. 7B. 12C. 8

The new library is open. Xiao Hong goes to the library every three days and Xiao Ling goes every four days. After Xiao Hong and Xiao Ling meet in the library one day, they may meet again in the library after () days A. 7B. 12C. 8

3 and 4 are coprime, so the least common multiple of 3 and 4 is their product: 3 × 4 = 12 (days); a: after 12 days, they may meet again in the library

The new library is open. Xiao Hong goes to the library every three days, and Xiao Ling goes every four days. How many days after Xiao Hong and Xiao Ling meet one another in the library?

20 days later

Given the square of a + the square of B + the square of C-2A + 4b-6c + 14 = 0. Find the value of C-A + B

The square of a + the square of B + the square of C-2A + 4b-6c + 14 = 0
The square of a - 2A + 1 + B + 4B + 4 + C - 6C + 9 = 0
The square of (A-1) + (B + 2) + (C-3) = 0
a=1 b=-2 c=3
c-a+b
=3-1-2=0

3. As shown in figure (3), to measure the distance between two points P and Q on the edge of the pond, Xiao Li takes two points a and B on the vertical line PM of PQ to make AB = PA, and then determines Pb at B
In this case, the length of BC measured is the length of PQ. Is Xiao Li's measurement correct? Please give reasons.

Right
∵BC⊥PB PQ⊥PB
∴∠CBA=∠QPA=90°
∵AB=PA ∠CAB=∠QAP
∴△CAB≌△QAP
∴BC=PQ

2 {4x-0.5} - 3 {1-6} - x + {2x-2} - {3x + 5}

2 {4x-0.5} - 3 {1-6} - x + {2x-2} - {3x + 5}
=8x-1-3+x/2-x+2x-2-3x-5
=(8x+x/2-x+2x-3x)-1-3-2-5
=13x/2-11

The volume of a cone is equal to that of a cylinder. The surface area of a cylinder is half of that of a cone. The height of a cone is 18 cm, and the height of a cylinder is 18 cm?

18 divided by 3 equals 6 cm, 6 times 1 / 2 equals 3
The answer is 3

There is a string of continuous integers - 53; - 52, - 51, ask the 100th

-There are 53 numbers from 53 to - 1. Plus a 0, there are 54 numbers. There are 46 numbers from 100 to 56
So the 100th number should be 46

Given the circle C: x ^ 2 + y ^ 2 + 2x-4y + 3 = 0, a tangent is drawn from a point P (x, y) outside the circle to the circle, the tangent point is m, O is the coordinate origin, and ┃ PM ┃ = ┃ Po ┃, the trajectory equation of point P is obtained

Circle C equation: (x + 1) ^ 2 + (Y-2) ^ 2 = 2, so center C (- 1,2), R ^ 2 = 2
Let the coordinates of point p be (x, y)
Then PM ^ 2 = | PC ^ 2-r ^ 2 = (x + 1) ^ 2 + (Y-2) ^ 2-r ^ 2 = x ^ 2 + y ^ 2 + 2x-4y + 3
|PO|^2=x^2+y^2
Because PM ┃ = ┃ Po ┃,
So x ^ 2 + y ^ 2 + 2x-4y + 3 = x ^ 2 + y ^ 2, we get the trajectory equation of point P: 2x-4y + 3 = 0
I'm going to replace the trajectory equation with y,
Get PM ^ 2 = (x + 1) ^ 2 + (1 / 2x + 3 / 4-2) ^ 2-2
=5/4（x^2+3/5x)+9/16
=5/4(x+3/10)^2+9/20
So when x = - 3 / 10, PM gets the minimum
So the coordinates of the smallest point P are (- 3 / 10,3 / 5)

Factorization of a3-2a2-4a + 3

a³-2a²-4a+3
=a³-2a²-3a-a+3
=a(a²-2a-3)-(a-3)
=a(a+1)(a-3)-(a-3)
=(a-3)(a²+a-1)

If the inequality 3y-2 of 4 > 5Y + 2 of 3 holds, then K=
If 1 / 3 (KX + 9) > 2x holds, then K=

1 / 3 * (KX + 9) > 2x,
If (K / 3-2) x + 3 > 0 is reduced, then K / 3-2 = 0, that is k = 6, and the original inequality becomes 3 > 0