Срочно сделайте1)49-9b²2)16a²-8ab+b²3)(c³-27)4)y³+3y²x+3yx²+x³

Решите задачу:

$1)49 - 9 {b}^{2} = | {a}^{2} - {b}^{2} = (a +b)(a - b) | = \\ = {7}^{2} - (3b) {}^{2} = (7 - 3b)(7 + 3b) \\ \\ 2)16a {}^{2} - 8ab + b {}^{2} = |a {}^{2} - 2ab + {b}^{2} = (a - b) {}^{2} | = \\ = (4a) {}^{2} - 8ab + b {}^{2} = (4a - b) {}^{2} \\ \\ 3)c {}^{3} - 27 = |(a - b)(a {}^{2} + ab + b {}^{2} )| = \\ = c {}^{3} - 3 {}^{3} = (c - 3)(c {}^{2} - 3c + 9) \\ \\ 4)y {}^{3} +3y {}^{2} x+3yx {}^{2} +x {}^{3} = |a {}^{3} + 3ab {}^{2} + 3a {}^{2}b + b {}^{3} = (a + b) {}^{3} | = \\ = (y + x) {}^{3}$