The big rectangle divides three small rectangles of the same size. The perimeter of the big rectangle is 8 decimeters. Calculate the area of the big rectangle

The big rectangle divides three small rectangles of the same size. The perimeter of the big rectangle is 8 decimeters. Calculate the area of the big rectangle

The answer is 3.84 square decimeters

The proof that LNX / x approaches 0 when x approaches infinity

First of all, the change of logarithmic function must be slower than that of ghost function. When x tends to infinity, the increase of X must be faster than that of INX. You can see it by drawing a picture
About the strict mathematical proof, in fact, it is also very simple. Infinity is bigger than infinity. It comes out with the law of lobita. The denominator is 1 and the molecular is 1 / X. The result is 1 / X. when x tends to infinity, naturally, the final result tends to 0!

If the equation x2 / (4-m) + Y2 / (M-3) = 1 represents an ellipse with focus on the Y axis, what is the range of M

X2 / (4-m) + Y2 / (M-3) = 1 represents the ellipse with the focus on the Y axis,
therefore
m-3＞4-m＞0
2m＞7
m＞7/2
m＜4
therefore
The range of M is 7 / 2 < m < 4

What is the remainder of a prime number greater than 6 divided by 6

7 divided by 6, the rest 1
11 divided by 6, 5,
It can only be these two numbers,
Because if we consider the possibility of all the remainder;
There are 1,2,3,4,5, obviously 2,4 is impossible. If the remainder is 2,4, the divisor is even and greater than 6, not prime
If the remainder is 3, then the divisor must be divisible by 3, because it is impossible to satisfy the condition that it is greater than 6. The sum up is only 1,5

Given that the inequality loga (x ^ 2-x-2) > loga (- x + 2x + 3) holds when x = 9 / 4, find the solution set of the inequality

Substitute x = 9 / 4 into x ^ 2-x-2 = 81 / 16-9 / 4-2 = 31 / 16 - x ^ 2 + 2x + 3 = - 81 / 16 + 9 / 2 + 3 = 39 / 16 because x ^ 2-x-2loga (- x ^ 2 + 2x + 3) so 00 (2) x ^ 2-x-22 or X

The same function as y = o.1 ^ LG (2x-1) is: a.y = 2x-1 (x > 1 / 2) b.y = 1 / (2x-1) C.Y = 1 / (2x-1) (x > 1 / 2) D.Y = | 1 / (2x-1)|

Select C
Obviously, it can be reduced directly, 10 ^ LG (2x-1) = 2x-1 (x > 1 / 2)
Then, o.1 ^ LG (2x-1) = 1 / (2x-1) (x > 1 / 2)
And multiple choice questions can have its special solution
If x of logarithm is more than 1 / 2, there are only a and C. then a special value of X is brought in to distinguish a and C

A prime number is a prime number after adding 10, and a prime number after adding 14. What is the prime number?

29

Edge probability density of two dimensional random variables
When you want to find the integral of Y, use the range of X, and finally DX. How do you find it when the middle part has both X and y? Please give an example to be specific. Now it's completely confusing

How to find the middle part with both X and y?
A: for example, the integral limit is x (1,2), and the probability density is f (x, y) = 2XY, so the product of the square of X and y after integration, so finally, we substitute x (1,2) into the square of X, and finally get the analytical formula with y

Let a > 0, when - 1 ≤ x ≤ 1, the minimum value of the function y = - x2 ax + B + 1 is - 4, and the maximum value is 0

Y = − x2 − ax + B + 1 = − (x + A2) 2 + A24 + B + 1; (1) if − A2 ≤− 1, i.e. a ≥ 2, the function y decreases monotonically on [- 1, 1]; {the minimum value of the function is B-A = - 4; the maximum value is a + B = 0, i.e. a = 2, B = - 2; (2) if − 1 ＜− A2 ＜ 0, i.e. 0 ＜ a ＜ 2, x = − A2, i.e

If two-thirds A is equal to three-quarters B, then a is equal to 9 to 8?

That's right