The absolute value of equation (x minus 2) = the number of real roots of lgx is

Combination of number and shape
y1=|x²-2|,y2=lgx
Draw a sketch of Y1 and Y2, easy to get: the image of Y1 and Y2 has two intersections
Abscissa is located in the interval (1, √ 2) and (√ 2, + ∞)
Therefore, the equation | X & # 178; - 2 | = lgx has two real roots

The number of real roots of the equation lgx = cosx is______ ．

The graph of the functions y = cosx and y = lgx is drawn

A is a third-order matrix, e is a third-order identity matrix, the three eigenvalues of a are 1,2, - 3 respectively, then the following matrices are invertible matrices: a.a-e B.A + e C.A + 3E d.a-2e why is the answer B?

If a + AE is reversible, it only needs | a + AE ≠ 0, that is, a is not the eigenvalue of - A, that is, - A is not the eigenvalue of A. therefore, a ≠ - 1, - 2,3 is OK. Observe the option, only a + e is reversible, select B

Known two-point coordinates to find the equation of the vertical line

Let two points be a (x1, Y1) B (X2, Y2), then the M coordinate of the midpoint of AB is ((x1 + x2) / 2, (Y1 + Y2) / 2). Because the slope of the straight line determined by two points of AB is (y2-y1) / (x2-x1), the slope of the middle vertical line is - (x2-x1) / (y2-y1) and passes through point m, so the equation is y = - (x2-x1) / (y2-y1) x + (Y1 + y

Is the degree of a monomial the same as the power of a monomial
It is said in the mathematics book of Beijing Normal University edition that the number of a single non-zero number is zero, and the zero power of a non-zero number is equal to 1

The zero power of a nonzero number equal to 1 means that when a is not equal to 0, a ^ 0 = 1
The degree of a non-zero number is zero. A non-zero number refers to a constant term that is not equal to zero. The constant term has no letter
For example, let's say - 5 = - 5 * 1 = - 5 * a ^ 0, so the number of times is 0, because the number of times of a monomial depends on the number of letters

Xiao Wang read a story book. On the first day, he read 6 pages more than 1 / 6 of the whole book. On the second day, he read 8 pages less than 1 / 8 of the whole book. Finally, there are 172 leaves left. How many leaves are there in this story book?

(172-8+6)/(1-1/6-1/8)
=170x24/17
=240 (page)

The M + 1 power of polynomial-1 / 2Ab + the square of AB-1 is a polynomial of degree six. The degree of the 3 a power of the monomial-3 / 5x multiplied by the 5-m power of Y multiplied by Z (complement problem)
With the same degree of polynomial, M.N

Both six times
So 1 + m + 1 = 6
3n+5-m+1=6
So m = 4
n=m/3=4/3

From place a to place B, the bus runs at the speed of 60 km / h, and the car starts 45 minutes later at the speed of 80 km / h
Get to B. find the distance between a and B

Timely adoption is conducive to the next answer
If the distance is x and the bus time is y, then the car time is y-45
For buses: x = 60 * y
For car: x = 80 * (y-45)
The two formulas are the same: 60 * y = 80 * (y-45) gives y = 180min = 3H
Then s = 60 * 3 = 180 km

The difference between length unit and unit length in number axis

A unit of length is a unit of length, such as meter, centimeter, millimeter
The unit length refers to a unit length, depending on the unit. If the unit is meter, the unit length is one meter

From city a to city B, the train takes 3 / 8 of the whole journey in 4 hours. At such a speed, how many parts of the whole journey can it take in 8 hours? How many parts are not finished?

1 hour 3 / 8:4 = 3 / 32; 8 hours 3 / 32x8 = 3 / 4; unfinished 1-3 / 4 = 1 / 4

The absolute value of equation (x minus 2) = the number of real roots of lgx is