123456+234561+345612+456123+561234+612345．

123456+234561+345612+456123+561234+612345．

123456+234561+345612+456123+561234+612345=111111+222222+333333+444444+555555+666666=（1+2+3+4+5+6）×111111=21×111111=（20+1）×111111=20×111111+111111=2222220+111111=2333331

How can 123456 be equal to 1

1+2+3-4+5-6=1

Why is the determinant of AB = the determinant of BA in a matrix?

There is a formula | ab | = | a | B|
Here | a | and | B | are numbers, so we can use the multiplication of numbers to exchange rates
|A||B| = |B||A| =|BA|
So equal

Let AB be a matrix of order n, and prove that ab Ba determinant = a + B determinant multiplied by A-B determinant requires block matrix and that formula

Validation (E, e * (a, b * (E - E)
0 E) B A) 0 E)
=（A+B 0
B A-B),
Where e is the unit matrix of order n. take determinants on both sides of the equation, and note the equality
The determinant of the right matrix is | a + B | * | A-B |