(2-1-11; 11-21; 36-97) is reduced to the simplest form matrix

(2-1-11; 11-21; 36-97) is reduced to the simplest form matrix

r1-2r2,r3-3r20 -3 3 -11 1 -2 10 3 -3 4 r3+r10 -3 3 -11 1 -2 10 0 0 3 r3*(1/3),r1+r3,r2-r30 -3 3 01 1 -2 00 0 0 1r1*(-1/3),r2-r10 1 -1 01 0 -1 00 0 0 1r1r21 0 -1 00 1 -1 00 0 0 1

How does A-4 - 25 A-1 - 25 - 6 a-49 become - 5 - 3 A + 7 A-1 - 3 A + 7 of A-1 a-49
If you mess up everything, it should be A1 (A-4 - 25) A2 (- 6a-49) A3 (- 5 - 3A + 7) a matrix is (A1 A2 A3) t
How to become B1 (A-1 - 25) B2 (A-1, a-49) B3 (A-1 - 3A + 7) B matrix is (B1, B2, B3) t
I mainly want to know how the first column of a matrix becomes the first column of B matrix. This is a step in the problem of ball eigenvalue. I can't understand it. In addition, a is actually the symbol of NAMDA, but I can't type it, so I replace it~

a-4 -2 5
-6 a-4 9
-5 -3 a+7
Add columns 2 and 3 to column 1
a-1 -2 5
a-1 a-4 9
a-1 -3 a+7
This is the best way to deal with the same row and can put forward a factor with λ!

VB programming to find the sum of elements on the main diagonal of the following matrix

In my understanding, you are a 9 * 9 matrix, then: dim s as integerdim I as integerdim J as integerdim D (9,9) As Integer 'suppose that the two-dimensional array is D, and the value of the main diagonal element is 1-9s = 0 for I = 1 to 9 for J = 1 to 9 If I = J then s = s

Given the absolute value a is equal to 3, B = (1,2), and a / / B, find the coordinates of B!

First of all, it's not the absolute value of a, it's the module length of A. It's the same as the sign of absolute value, but it's two concepts
Secondly, we should find the coordinates of a instead of B
A / / b let a = (x, 2x)

Finding the definition field of function f (x) = x ^ 2-2x-3 / root X-1

Inside the radical
x-1>=0
x>=1
Denominator ≠ 0
Namely
x²-2x-3≠0
(x+1)(x-3)≠0
X ≠ - 1 and X ≠ 3
therefore
x> = 1 and X ≠ 3

Find the number of zeros of the function f (x) = ln (x-1) + 2x

Let g (x) = ln (x-1) and H (x) = - 2x, then the number of zeros of F (x), that is, the number of intersections of G (x) and H (x) on the interval (1, + ∞), is determined. In the coordinate system, the images of G (x) = ln (x-1) and H (x) = - 2x are made simultaneously

Let FX be an increasing function on R, FX = fx-f (2-x), and prove that FX is an increasing function on R

F (x) increasing function
2-x is a decreasing function
therefore
F (2-x) is a decreasing function
Namely
-F (2-x) is an increasing function
therefore
FX = fx-f (2-x) is an increasing function

Judgment: when a is a rational number, the absolute value of a is greater than or equal to a

Yes!

Can a gerund phrase be the subject of a sentence?

Reading in the sun is not good for our eyes

If a, B, C and D are four positive numbers and ABCD = 1, find the value of (A / ABC + AB + A + 1) + (B / BCD + BC + B + 1) + (C / CDA + CD + C + 1) + (D / DAB + Da + D + 1)

a/(abc+ab+a+1)+b/(bcd+bc+b+1)+c/(cda+cd+c+1)+d/(dab+da+d+1)=a/(1/d+ab+a+1)+b/(bcd+bc+b+1)+c/(1/b+cd+c+1)+d/(dab+da+d+1)=ad/(abd+ad+d+1)+b/(bcd+bc+b+1)+bc/(bcd+bc+b+1)+d/(dab+da+d+1)=(ad+d)/(abd+ad+d+1...