Factorization of x ^ 4-25x ^ 2

Factorization of x ^ 4-25x ^ 2

x⁴- 25x²
= x² ( x² - 25)
= x² (x+5)(x-5)

Given x2 + y2-6x-8y + 25 = 0, find the value of the algebraic formula YX − XY

∵ x2 + y2-6x-8y + 25 = 0, ∵ (x-3) 2 + (y-4) 2 = 0, ∵ x = 3, y = 4, when x = 3, y = 4, the original formula = 43-34 = 712

If x ^ 2-6x + y ^ 2 + 8y + 25 = 0, then x = how much, y = how much

If x ^ 2-6x + y ^ 2 + 8y + 25 = 0, then x = 3, y = - 4
x²-6x+y²+8y+25=0
x²-6x+9+y²+8y+16=0
(x-3)²+(y+4)²=0
x-3=0 y+4=0
∴x=3 y=-4

9 / 25 - (X-Y) to the second power (factorization,

(9/25)-(x-y)²=(3/5)²-(x-y)²=(0.6-x+y)(0.6+x-y)

1 × 2 / 1 plus 2 × 3 / 1 plus 3 × 4 / 1 plus... Plus 9 × 10 / 1 is equal to (1 / 1 minus 2 / 1) + (1 / 2 minus 3 / 1)
1 × 2 / 1 plus 2 × 3 / 1 plus 3 × 4 / 1 plus... Plus 9 × 10 / 1 is equal to (1 / 1 minus 2 / 1) + (1 / 2 minus 3 / 1) + (1 / 3 minus 4 / 1) +... + (1 / 9 minus 10 / 1)
Solve the equation according to the above method
1 of X (x + 2) plus 1 of (x + 2) (x + 4) minus 1 of 2x equals 1

The original formula = (1-1 / 2) + (1 / 2-1 / 3) + (1 / 3-1 / 4) + (1 / 9-1 / 10)
=1-1/0
=9/10

The surface area of a cuboid is 160 square decimeters. If you saw it into two identical cubes, how many square decimeters more than the original surface area?

Because the surface area of a cuboid is 160 square decimeters, saw it into two identical cubes, its surface area increased by 2 small squares
Two identical cubes are: 6 × 2 = 12 (faces)
The original cuboid has 12-2 = 10 faces
The area of each surface is: 160 △ 10 = 16 (square decimeter)
Its surface area is increased: 16 × 2 = 32 (square decimeter)

1 divided by () = what's 12% = 12 to () = 75% = 30

1 divided by (4 / 3) = 12% (9) = 12 vs (16) = 75% = (22.5) divided by 30

1. For any positive integer n, the integer that can divide the algebraic expression (3N + 1) (3n-1) - (3-N) (3 + n) is () 2
1. For any positive integer n, the integer that can divide the algebraic expression (3N + 1) (3n-1) - (3-N) (3 + n) is ()
2. If (X-5) ² = x & #178; + KX + 25, then k = ()
3. If X & # 178; + 4x + K & # 178; is exactly the square of another integer, then the value of constant k is ()
4. If A-B = 2, a-c = 1, then the value of (2a-b-c) &# 178; + (C-B) &# 178; is ()

5,3,2,6

Magic square, respectively, 29, 30, 31, 32, 33, 34, 35, 36, 37 fill in, so that the horizontal, vertical and oblique add up to 99

34 35 30
29 33 37
36 31 32

How to simplify: (1-1 / A + 1) * the square of a + 2A + 1 / a

The original formula = (a + 1-1) / (a + 1) * (a + 1) & # / A
=a/(a+1)*(a+1)²/a
=a+1