Let a ∈ r solve the inequality x (x-a + 1) about X

Let a ∈ r solve the inequality x (x-a + 1) about X

When x (x-a + 1) - 1, - 1

Solving differential equation. (xlnx) y '+ y = xlnx

The general solution of the homogeneous equation (xlnx) y '+ y = 0 ∵ (xlnx) y' + y = 0 = = > (xlnx) dy / DX = - y = = > dy / y = - DX / (xlnx) = = > dy / y = - D (LNX) / LNX = = = > ln ∵ y ∵ = - ln ∵ LNX ∵ + ln ∵ (C is an integral constant) = = = = > y = C / LNX ∵ homogeneous equation (xlnx) y '+ y = 0 is y = C / LNX (C

Observe the following series of numbers: 2 / 3, 3 / 8, 5 / 24, then what is the seventh number? What is the law? It is expressed by n

Molecules
2,3,4,5, the nth is n + 1
denominator
3=2²-1
8=3²-1
15=4²-1
24=5²-1
The nth is (n + 1) & sup2; - 1 = n & sup2; + 2n
So the seventh = (7 + 1) / (7 & sup2; + 2 * 7) = 8 / 63
Nth = (n + 1) / (n & sup2; + 2n)

Write the division formula with 9 numbers from 1 to 9 that the divisor is a two digit number (the number cannot be repeated)

5346/27=198
4396/28=157
5796/12=483
5796/42=138
5346/18=297
7254/39=186
7632/48=159

In the space rectangular coordinate system, given the points a (1,0,2), B (1, - 3,1), the point m is on the Y axis, and the distance from m to a and B is equal, then the coordinate of M is ()
A. （0，-1，0）B. （0，1，0）C. （1，0，1）D. （0，1，1）

Let m (0, y, 0) get y = - 1 from 12 + Y2 + 4 = 1 + (y + 3) 2 + 1, so m (0, - 1, 0) is selected: a

There are two intersection points between the straight line y = kx-1 and the hyperbola 4x2-9y2 = 36. Find the value range of the real number K

Y = kx-1
4x²-9（kx-1)²=36
（4-9k²）x²+18kx-45=0
Because there are two intersections
So the discriminant is greater than 0
324k²+180（4-9k²）>0
-324k²+180>0
9k²

There is a math problem: 9 7 5 4 = 24, fill in the arithmetic symbol, urgent. (can add brackets))
You can't change the order of the numbers. For example, someone just answered that (9-5) × 7-4 = 249 + (7-4) * 5 = 244 times 9 minus 5. The sum is wrong. You can't change the order. Example 5 and 7 can't be exchanged, or you've already worked it out. I don't understand square brackets

If you can add the square sign, then (9-7) square × 5 + 4

If positive real numbers a and B satisfy log2 (a) + log2 (3b) = 0, then the minimum value of 3 ^ A + 27 ^ B
The formula of logarithm is reduced to 3AB = 1.3 ^ A + 27 ^ B ≥ 2 √ 3 ^ 3AB = 2 √ 3

3^a+27^b
=3^a+3^(3b)
≥2√[3^a*3^(3b)]
=2√[3^(a+3b)]
≥2√3^(2√(a*3b))
=2√3^(2*1)
=2√3^2
=2*3
=6
You have multiplied 3 ^ A * 3 ^ (3b) by mistake

It is known that a rectangle with side lengths of a and 2B (a > b) is divided into four congruent right triangles, as shown in Figure 1, and then the four triangles are put together to form a square as shown in Figure 2, forming a hole in the middle of the square. The area of the rectangle is 24, and the side length of the square is 5. Try to find the value of A2 + B2 and A2-B2 through the information you get

According to the meaning of the title, A2 + B2 = 52 = 25, a · 2B = 24, ∧ A2 + B2 + 2ab49, ∧ a + B = 7, ∧ a > b, ∧ a = 4, B = 3, ∧ A2 + B2 = 25, A2-B2 = 7

The problem of set containing symbols (Mathematics)
Look at the symbols:
A &; B: if all elements of a set are elements of B at the same time, a is called a subset of B
If a is a subset of B and a is not equal to B, then a is called a proper subset of B
I understand these two symbols. There's another kind of symbol, which is, does it have the same meaning as a and B?

Yes, there is a ≠ meaning "true inclusion" below, which is equivalent to a and B