Ta có: (2x-1)^3 + (5-6x)^3 -4^3 (1-x)^3

= (2x-1)^3 + (5-6x)^3 -(4-4x)^3    (*)

Đặt 2x-1 = a và 5 -6x = b thì 4-4x = a+b nên thay vào (*),ta được : 

   a^3+ b^3 -(a+b)^3

= a^3 +b^3 -a^3-b^3 -3ab(a+b)

= -3ab(a+b)

= -3 (2x-1)(5-6x)(4-4x)

Chúc bạn học tốt.

f) \(x^2-6x+5=\left(x^2-x\right)+\left(-5x+5\right)=x\left(x-1\right)-5\left(x-1\right)=\left(x-1\right)\left(x-5\right)\)

g) \(x^4+64=\left(x^2+4x+8\right)\left(x^2-4x+8\right)\)

\(x^2-6x+5\)

\(=\left(x^2-2.3x+3^2\right)-4\)

\(=\left(x-3\right)^2-2^2\)

\(=\left(x-3-2\right)\left(x-3+2\right)\)

\(=\left(x-5\right)\left(x-1\right)\)

\(=6x^2+3x+10x+5=3x\left(2x+1\right)+5\left(2x+1\right)=\left(3x+5\right)\left(2x+1\right)\)

6x2+3x+10x+5=3x(2x+1)+5(2x+1)=(3x+5)(2x+1)

a)   x² - 6x + 9 - 16 = x² - 6x - 7 = x² + x - 7x - 7 = x(x+1) - 7(x+1) = (x-7)(x+1)

b) x⁴ - 64 =  (x² - 8)(x² + 8)

(x²  - 2.x.3 +3² ) - 4²

(x-3)² - 4² 

(x-3-4)(x-3+4)

b)

(x²)² - 8² 

(x²-8)(x²+8)

C1: 

x²-6x+5=x²-x-5x+5=(x²-x)-(5x-5)=x(x-1)-5(x-1)=(x-5)(x-1)

C2: 

x²-6x+5= (x²-6x+9)-4=(x-2)²-2²=(x-2-2)(x-2+2)=x(x-4)

mới 2 cách thôi mà ;-;

Bài 1 :

\(x^2-6x+8=x^2-2x-4x+8=x\left(x-2\right)-4\left(x-2\right)=\left(x-4\right)\left(x-2\right)\)

Bài 2 :

 \(x^8+x^7+1=x^8+x^7+x^6+x^5+x^4+x^3+x^2+x+1-x^6-x^5-x^4-x^3-x^2-x\)

\(=x^6\left(x^2+x+1\right)+x^3\left(x^2+x+1\right)+x^2+x+1-x^4\left(x^2+x+1\right)-x\left(x^2+x+1\right)\)

=\(\left(x^2+x+1\right)\left(x^6+x^3+1-x^4-x\right)\)

Tick đúng nha 

X^2-6+8

\(=2x\left(x+3\right)\)

64-96a+48a²-8a^3= 4³ - 3.4².21 +3.4.(2a)² - (2a)³= (4-2a)³

a) (4- 2a)³

\(=6x\left(-y^2+x^2+2x+1\right)\\ =6x\left[\left(x^2+2x+1\right)-y^2\right]\\ =6x\left[\left(x+1\right)^2-y^2\right]\\ =6x\left(x+1-y\right)\left(x+1+y\right)\)