Set a = {(x, y) | x ^ 2 + mx-y + 2 = 0} B = {(x, y) | X-Y + 1 = 0,0

Set a = {(x, y) | x ^ 2 + mx-y + 2 = 0} B = {(x, y) | X-Y + 1 = 0,0

This is a problem of the distribution of the roots of quadratic equation of one variable
∵x^2+mx-y+2=0 ∴y=x^2+mx+2
∵ a intersection B is not an empty set
The equation x ^ 2 + MX + 2 = x + 1 at 0

I was wrong just now
Let the set a = {x | x2 + (P + 2) x + 1 = 0}, and the intersection R + = ф, find the value range of real number P

A ∩ R + = empty set, indicating that the equation x & sup2; + (P + 2) x + 1 = 0 has no positive root
There are two situations
(1) A = empty set
The equation has no solution and the discriminant is less than 0
(p+2)²-4

The known set a = {x | x ^ 2-x-6 > 0} B = {x | 0}

A={x3}
B={-a

Given the set a = {(x, y)} | x2 + mx-y + 2 = 0}, B = {(x, y) | X-Y + 1 = 0,2 ≥ x ≥ 0}, if a ∩ B ≠?, find the value range of real number m according to my method
I did it
There are two equations because there is a common part. Equation 1 minus equation 2
x2+（m-1）x+1=0
M-1 = - x 2 + 1
M = - (x + 1 / x) + 1, X ∈ (0,2]
I want to know the range of X + 1 / X

Let g (x) = x + 1 / x, its image can be made. This is an odd function. The domain of definition is x not equal to 0. The image is called "check function". Its range is greater than or equal to 2 or less than - 2

The form of transforming 2x2 + 4x-1 into a (x + H) 2 + K (where a, h, K are constants) is ()
A. 2（x+1）2-3B. 2（x+1）2-2C. 2（x+2）2-5D. 2（x+2）2-9

Let y = 2x2 + 4x-1, according to the properties of quadratic function, the vertex coordinates of this quadratic function are x = - 42 × 2 = - 1, y = 4 × 2 × (− 1) − 164 × 2 = - 3, so the quadratic function y = 2x2 + 4x-1 can be changed into y = 2 (x + 1) 2-3

Bracket formula 280 + 320 / 40-32 * 2 = 150

(280+320)/(40-32) *2=150

The following formula: ① - x ② (M + n) / 3 ③ Y / X ④ A & # 178; - B & # 178; ⑤ (- X & # 178; y) / 4 ⑥ X / 2 + 3x + y. the problem is as follows:
Among them, the monomials are__________ Of polynomials are________ Of integral______ (insert serial number)

1,5 are monomials
2,4 are polynomials
1,2,4,5 are integers

3 times 5 numerator 1 plus 5 times 1 in 7 plus 7 times 1 in 9 plus 9 times 1 in 11. Plus 1997 times 1 in 1999 =?

3 times 5 molecules 1 plus 5 times 7 parts 1 plus 7 times 9 parts 1 plus 9 times 11 parts 1. Add 1997 times 1999 parts 1 = 1 / 2 (1 / 3-5 parts 1) + 1 / 2 (1 / 5-7 parts 1) + 1 / 2 (1 / 1997-1999 parts 1) = 1 / 2 (1 / 3-5 parts 1 + 5 parts 1-7 parts 1. + 1997 parts 1-1999 parts 1) = 1 / 2 *

Multiplication of three polynomials (x-1) (x + 1) (2x + 1)
(x-1)(x+1)(2x+1)=?

(x-1)(x+1)(2x+1)=(x²-1)(2x+1)=2x³+x²-2x-1

For a bottle of alcohol, pour out 2 / 3 and 20 bottles for the first time, then pour back 35 grams, and pour out the remaining 1 / 2 for the second time. At this time, there are still 45 grams left in the bottle, which is the same as that in the original bottle
How many grams of alcohol are there

225 grams. If it's 20 grams, the answer is 225 grams