Decomposition factor: X4 + 4 X4 + 4 = X4 + 4x2 + 4-4x2 = (x2 + 2) 2-4x2 = (x2 + 2x + 2) (x2-2x + 2) In the above solution, add a term in the middle of X4 + 4, so that the three terms form a complete square formula. In order to keep the value of this formula unchanged with the value of X4 + 4, the same term must be subtracted. According to this idea, try to factorize the polynomial x ^ 4 + x ^ 2-2ax + 1-A ^ 2

The original formula = (x ^ 4 + 2x & # 178; + 1) - (X & # 178; + 2aX + A & # 178;) = (X & # 178; + 1) & # 178; - (x + a) & # 178; = (X & # 178; + X + A + 1) (X & # 178; - x-a + 1)

In C language: & = and equal, | = or equal, what do these two expressions mean?

a&=b; == a=a&b;
a|=b; == a=a|b;

Add 3 4 9 15 14 according to the rule

21 27 24 33

A natural number is divided by 3,4,5, the remainder is 2,3,4 respectively, and the sum of the three quotients is 87. What is the natural number?

3x + 2 = P 4Y + 3 = P 5Z + 4 = P x + y + Z = 87 solve this system of equations. Four equations and four unknowns must have solutions

What are the formulas for friction?

f=u*N
U is the coefficient of friction, which is related to the roughness of material and object surface
N is the positive pressure, remember it must be perpendicular to the friction force, usually with downward pressure plus gravity
Remember that the direction of friction on the conveyor belt is the same as the direction of motion
Walking is static friction

2,5,6,10,（）,20,54,（ )

2,5,6,10,18,20,54,40

The sum of all the natural numbers from 1 to 1001 is______ ．

According to the meaning of the title: in 1-999, each number of 1-9 appears 100 times in 100, 10, and one place, so the sum of all numbers in 1-999 is: (1 + 9) × 9 △ 2 × 100 × 3 = 13500; the sum of 1000 and 1001 is: 1 + 1 + 1 = 3; so the natural number 1 23 45 In 1001, the sum of all numbers is: 13500 + 3 = 13503

A = 4 + 2 + 1, find 2 / A + 2 / A * 2 + 1 / A * 3

2 / A + 2 / A * 2 + 1 / A * 3 is wrong? A * 2, a * 3 means the second and third power of A. the cubic root of a = 4 + the third root of 2 + the third root of 1, that is, a = 4 ^ (1 / 3) + 2 ^ (1 / 3) + 1 ^ (1 / 3) = 2 ^ (2 / 3) + 2 ^ (1 / 3) + 1. From the cubic difference formula, we can know x ^ 3 - y ^ 3 = (X-Y) * (x ^ 2 + XY + y ^ 2)

64 81 100 121 144 ___ Find out what the last number is according to the law

8×8,9×9,10×10,11×11,12×12,13×13
So the last number is 13 × 13, which is 169

Simplification: 1 / 2x-1 / (x + y) [(x + y) / 2 - (2x & # 178; + 2XY) / 2x]

Original formula = 1 / 2x-1 / (x + y) [(x + y) / 2 - (x + y) / 2]
=1/2x-1/(x+y).0
=1/2x