Question

помогите (15 балов) ......,.,.,.,.,.,.,.,..,.,.,.,.,.,..,.,.,​

Answer 1

1. $5 {a}^{2} - 125a {b}^{2} = 5( {a}^{2} - 25 {b}^{2} ) = 5(a - 5b)(a + 5b)$
2. ${a}^{2} - {b}^{2} - 5a + 5b = (a - b)(a + b) - 5(a - b) = (a - b)(a + b +5)$
3. ${a}^{2} - 2ab + {b}^{2} - ac + bc = {(a - b)}^{2} - c(a - b) = (a - b)(a - b - c)$
4. $25 {a}^{2} + 70ab + 49 {b}^{2} = {(5a + 7b)}^{2}$
5. ${a}^{2} - 2ab + {b}^{2} - 3a + 3b = {(a - b)}^{2} - 3(a - b) = (a - b)(a - b - 3)$
6. $63a {b}^{3} - 7 { a}^{2} b = 7ab(9 {b}^{2} - a) = 7ab(3b - \sqrt{a} )(3b + \sqrt{a} )$
7. $(b - c)(b + c) - b(b + c) = - c(b + c)$
8. ${m}^{2} + 6mn + 9 {n}^{2} - m - 3n = {(m + 3n)}^{2} - 1(m + 3n) = (m + 3n)(m + 3n - 1)$
9. ${a}^{2} - 9 {b}^{2} + a - 3b = (a - 3b)(a + 3b) + 1(a - 3b) = (a - 3b)(a + 3b + 1)$
10. $4 {a}^{3} - a {b}^{2} = a(4 {a}^{2} - {b}^{2} ) = a(2a - b)(2a + b)$