Question

разложите на множители
1)a² - 2 ab + b² - 25
2)x² - 16b²+8bc - c²
3)a³x² - ax - 4a³ - 2a
4)a³ - 27 + a² - 3a
5)b¹⁰ - 25b⁸ - 40b⁴ - 16
6)8a³- 27b³+ 4a³- 12 ab + 9b²
7)4x² - 12xy + 9y² - 4a² + 4 ab - b²
8)x² - y²- 6x + 9​

Answer 1

$\displaystyle \tt 1) \: a^2-2ab+b^2-25=(a-b-5)(a-b+5)\\\displaystyle \tt 2) \: x^2-16b^2+8bc-c^2=(x-4b+c)(x+4b-c)\\\displaystyle \tt 3) \: a^3x^2-ax-4a^3-2a=a(x+2)(a^2x-2a^2-1)\\\displaystyle \tt 4) \: a^3-27+a^2-3a=(a-3)(a^2+4a+9)\\\displaystyle \tt 5) \: b^{10} - 25b^8 - 40b^4 - 16=(b^5+5b^4+4)(b^5-5b^4-4)\\\displaystyle \tt 6) \: 8a^3-27b^3+4a^3-12ab+9b^2=3(4a^3-9b^3-4ab+3b^2)\\\displaystyle \tt 7) \: 4x^2-12xy+9y^2-4a^2+4ab-b^2=(2x-3y-2a+b)(2x-3y+2a-b)\\$

$\displaystyle \tt 8) \: x^2-y^2-6x+9=(x-3-y)(x-3+y)$

Answer 2

1) $a^2 - 2ab + b^2 - 25 = (a - b)^2 - 25 = (a - b -5)(a - b + 5)$

2) $x^2 - 16b^2+8bc - c^2 = x^2 - (16b^2 - 8bc + c^2) = x^2 - (4b - c)^2 = (x - 4b + c)(x - 4b - c)$

3) $a^3x^2 - ax - 4a^2 - 2a = a(a^2x^2 - x - 4a - 2)$

4)$a^3 - 27 + a^2 - 3a = (a-3)(a^2+4a-9)$

5)$b^{10} - 25b^8 - 40b^4 - 16 = (b^5 - 5b^4 - 4)(b^5 + 5b^4 + 4)$

6)$8a^3- 27b^3+ 4a^3- 12ab + 9b^2 = 12a^3 - 27b^3 - 12ab + 9b^2 = 3(4a^3 - 9b^3 - 4ab + 3b^2)$

7)

$4x^2 - 12xy + 9y^2 - 4a^2 + 4ab - b^2 = (2x - 3y)^2 -(2a - b)^2 = (2x - 3y - 2a \\\\+ b)(2x - 3y - 2a-b)$

8)$x^2 - y^2- 6x + 9 = x^2 - 6x + 9 - y^2 = (x-3) - y^2 = (x-3-y)(x-3+y)$