1) b³ - 8c³ = b³ - (2c)³ = (b-2c)(b² + 2bc + 4c²)
2) 49yx² - y³ = y(49x² - y²) = y (7x-y)(7x+y)
3) -7a² + 14a - 7 = -7(a² - 2a + 1) = -7(a-1)²
4) 5ab - 15b - 5a + 15 = 5b(a-3) - 5(a-3) = 5(a-3)(b-1)
5) a⁴-1 = (a²-1)(a²+1) = (a-1)(a+1)(a²+1)
4x-|x-2|-3=0
1) x≤2 2) x>0
4x+(x-2)-3=0 4x-(x-2)-3=0
4x+x-5=0 4x-x+2-3=0
5x=5 3x=1
x=1∈(-∞;2] x=1/3∉(2;+∞)
Ответ: 1
9^3 * b^3/b^7 * b^3 =9^3 / b
81= 9^2
9^3 / 9^2 = 9