∣ x2 MX ∣ = 2, there are three real solutions, find the value of M

Because ∣ X & sup2; - MX ∣ = 2, there are three real number solutions, find the value of M, because ∣ X & sup2; - MX ∣ = 2, so: X & sup2; - MX = 2 or X & sup2; - MX = - 2, so: X & sup2; - mx-2 = 0 or X & sup2; - MX + 2 = 0, because ∣ X & sup2; - MX ∣ = 2, there are three real number solutions, then: X & sup2; - MX + 2 = 0, there are two same real number solutions, so: △ = M & sup

Inverse scale function (15:17:24:47)
The inverse scale function y = K / X and the first-order function y = 2x-1 are known, where the image of the first-order function passes through the point (k, 5)
(1) Try to find the analytic expression of inverse proportion function
(2) If point a is in the first quadrant and on the image of the above two functions at the same time, calculate the coordinates of point a

(1) Because the linear function y = 2x-1, the image passes through the point (k, 5), so 2k-1 = 5, so k = 3,
So the analytic expression of inverse proportion function is y = 3 / X
(2) The abscissa of point a is the solution of equation 3 / x = 2x-1,
From the solution of equation 3 / x = 2x-1, we can get x = - 1 or x = 3 / 2, because point a is in the first quadrant, so x = 3 / 2, so y = 2,
So the coordinates of point a are (3 / 2,2)

Let y = (n ∧ 2 + n) X-2 (where n is a positive integer), when n = 1,2,3 At 20, the line Y1 = 2x-2, y2 = 6x-2, Y3 = 12x-2 The intersection points of X-2 and X-axis are A1, A2, A3 respectively A20, the point of intersection with y axis is B, the origin of coordinate is O, let the area of triangle a1ob be S1, the area of triangle a2ob be S2 If the area of triangle a20ob is S20, then (1) S1 + S2 = &# 160; &# 160; &# 160; &# 160; (2) S1 + S2 + S3 + S20=

There are two fixed points: origin O and B (0, - 2). You just need to find the law of point a
A1(1,0) A2(1/3,0) A3(1/6,0)
In fact, it is to find the sum of money 20 terms of 1 / (n Λ 2 + n), which can be obtained by the split term offset method
1/(n∧2+n) = 1/n - 1/(n+1)
I've sent you the idea of solving the problem. Let's do the rest by ourselves

{1,2,3,4,5,… }Is a set of natural numbers: {1,4,9,16,25 }It's a set of natural number squares
{1,2,3,4,5,… }Is a set of natural numbers:
{1,4,9,16,25,… }Is the set of natural number squares
These two sets of numbers can easily form a one-to-one correspondence. So, are there as many elements in each set?

It must be wrong

There are a lot of fish in a fish pond in a fish farm. To know how many fish there are in a fish pond, the fishermen came up with a clever way: they first picked up 30 fish from a fish pond, made a mark for each fish, and then put them back in the fish pond. The fish went back to the water and swam around eight minutes. After a few days, the marked fish were evenly distributed in all parts of the pond Fang. The fishermen picked up another 50 fish from the pond and found two of them marked. How many fish are there in the pond?

The inequality x ^ 4 + (m-2) x ^ 2 + (5-m) > 0 holds for any real number X
The inequality x ^ 4 + (m-2) x ^ 2 + (5-m) > 0 holds for any real number x, and the value range of real number m is obtained
Also, if the title tells you that the inequality xxxxx holds for any real number x, what does it mean?

The inequality xxxxx holds for any real number X
It depends on what kind of inequality is
Generally speaking, there are two situations:
1. We can take appropriate coefficients so that the original inequality does not contain x, so that the inequality holds for any X
In this case, the undetermined coefficient method is enough
2. We can't change the coefficient of the term containing x to 0, but we should discuss it through other methods
This problem is a quadratic function, which is a special form of the second case
You can get it by changing yuan
x^2=t, t>=0
t^2+(m-2)t+(5-m)>0
There are two cases in which this formula holds for any X
1. The equation without real root is discriminant

Number a and number B are two double digits. 2 / 7 of number a is equal to 2 / 3 of number B. find the maximum difference between the two numbers

Because 2 / 7 of the number a is equal to 2 / 3 of the number B, so the number a is greater than the number b = 2 / 7:2 / 3 = 7:3, the greater the difference between the two numbers is, the greater the number a is. Because the number a and the number B are two double digits, the maximum number a is
7 × 14 = 98, then B = 3 × 14 = 42, 98-42 = 56

How to calculate the 300th power of 2

Enter in any cell of Excel: = 2 ^ 300
The results showed that: 2.0370359763449e + 90

A car from a city to B city, 40 kilometers per hour, from B city back to a city, 60 kilometers per hour

Average speed of round trip = 2 ^ (1 ^ 40 + 1 ^ 60) = 48 km / h

As shown in the figure, in triangle ABC, angle a = 80 degrees

According to the meaning of the title, the point O is the outer center of the triangle ABC, the circular angle a to which the arc is directed, and the central angle BOC to which the arc is directed is equal to twice the circular angle

∣ x2 MX ∣ = 2, there are three real solutions, find the value of M