The equivalent proposition to the proposition "if a ∈ m, then B ∉ m" is () A. . if & nbsp; a ∉ m, then & nbsp; B ∉ MB. If B ∉ m, then & nbsp; a ∈ MC. If & nbsp; a ∉ m, then & nbsp; B ∈ MD. if B ∈ m, then & nbsp; a ∉ M

The equivalent proposition to the proposition "if a ∈ m, then B ∉ m" is () A. . if & nbsp; a ∉ m, then & nbsp; B ∉ MB. If B ∉ m, then & nbsp; a ∈ MC. If & nbsp; a ∉ m, then & nbsp; B ∈ MD. if B ∈ m, then & nbsp; a ∉ M

∵ the original proposition and the inverse no proposition are equivalent to each other, and the proposition equivalent to the proposition "if a ∈ m, then B ∉ m" is: if B ∈ m, then & nbsp; a ∉ M. therefore: D

Proposition formula A and B are equivalent meanings

I think that a and B are also mutually sufficient and necessary conditions, which can be converted to each other, but not equal to each other. This is my idea, and we need to correct the following problems_ XJ's answer should be C owes A20 yuan, others or agree

"Proposition a and B are opposite to each other, no proposition" is the essence of "proposition a and B are equivalent to each other"___________________ Conditions

Proposition a and proposition B are opposite to each other, which is a sufficient condition for proposition a and proposition B to be equivalent to each other

28,45,3.6, - 3,0,11:9987,2:3, - 7:3,8.25, positive number has (), negative number has (), natural number has (), integer
Number has (), decimal has (), fraction has ()

The positive numbers are (28,45,3.6,9 / 11,987,2 / 3,8.25),
Negative numbers are (- 3, - 3 / 7),
The natural numbers are (28,45,0,987),
The integers are (28,45, - 3,0,987),
The decimals are (3.6, 8.25),
The score is (9 out of 11, 2 out of 3)

Let's see how to do a problem of finding rules in Mathematics in grade two () 13 24 36 43 54 45 47 18 30 ()

(7) 13 24 36 43 54 45 47 18 30 (37)
Take 54 as the center, then 54-43 = 11 on the left, 54-45 = 9 on the right, 54-47 = 7, 45-47 = - 2 on both sides, not 11 on both sides, then 54-24 = 30 on the left, 54-36 = 18 on the right, and then backward on the right, left 24 - (54-43) = 13, right 30 + (54-47) = 37, then backward 30 + 18 = 48, left 13 - (54-48) = 7

Given that n is a positive integer and n ^ 4 + 16N ^ 2 + 100 is a prime, find the value of n
Note that n ^ 4. "+"

It can't be prime
n^4+16n²+100 = n^4+20n²+100-4n²
= (n²+10)²-(2n)²
= (n²+2n+10)(n²-2n+10).
From n & # 178; + 2n + 10 > n & # 178; - 2n + 10 = (n-1) &# 178; + 9 > 1, n ^ 4 + 16N & # 178; + 100 is the product of two integers greater than 1, which cannot be prime

If the image of exponential function is over (- 1,2), then the exponential function is

Y = (1 / 2) ^ x, y is equal to the x power of 1 / 2

What world the next number be?4、7、13、25、49

The difference is an equal ratio sequence
3. 6, 12, 24, so the next difference is 48
So 49 + 48 = 97, next number is 97

How to factorize x ^ M-1

The original formula = (x-1) [x ^ (m-1) + x ^ (m-2) + +x^2+x+1]

On the application of quadratic equation of one variable in the third grade of junior high school
In a chess match, each player has just one match with the other players. The winner of each game gets 2 points and the loser gets 0 points. For example, in a draw, each of the two players gets one point. Today, four students have counted the total scores of the players in the game, which are 365 points, 380 points, 381 points and 400 points respectively. After verification, only one student has counted correctly

First of all, every game, no matter how the results are 2 points, so the total score is odd, it must be wrong
Suppose there are n players participating in the competition, then the number of matches must be cn2 (choose two combinations within n)
N (n-1) / 2, so the total score should be n (n-1)
The results of the other two groups were compared
n（n-1）=380
The solution is n = 20 or n = - 19, take n = 20, feasible
N (n-1) = 400, the solution is not integer, so it is incorrect
The correct total score is 380