2a³+54b⁶
x³-yx-x²+yx²
a+5b+a²-25b²
ac⁶-ac⁴-c⁶+c⁴​

1) 2a³ + 54b⁶ = 2(a³ + 27b⁶) = 2(a + 3b²)(a² - 3ab² + 9b⁴​)

2) x³ - yx - x² + yx² = x(x² - y - x + yx) = x(x² - y - x + xy) = x(x(x - 1) + y(-1 + x)) = x(x - 1)(x + y)

3) a + 5b + a²- 25b² = a + 5b + (a - 5b)(a + 5b) = (a + 5b)(1 + a - 5b)  

4) ac⁶ - ac⁴ - c⁶ + c⁴​ = c⁴(ac² - a - c² + 1) = c⁴(a(c² - 1) - (c² - 1)) = c⁴(c² - 1)(a - 1) = c⁴(c - 1)(c + 1)(a - 1)