Question

помогите решить последнее пж​

Answer 1

Объяснение:

$a)4 {a}^{2} - 1 = {2}^{2} {a}^{2} - {1}^{2} = (2 a)^{2} - {1}^{2} = (2a - 1)(2a + 1) \\ b) {x}^{3} - {xy}^{2} - 6 {y}^{2} + 6 {x}^{2} = x( {x}^{2} - {y}^{2} ) + 6( - {y}^{2} + {x}^{2} ) = ( {x}^{2} - {y}^{2} )(x + 6) = (x - y)(x + y)(x + 6) \\ c)9 {y}^{2} - 6y + 1 - 4 {y}^{4} = - 4 {y}^{4} + 9 {y}^{2} - 6y + 1 = - 4 {y}^{4} + 4 {y}^{3} - 4 {y}^{3} + 4 {y}^{2} + 5 {y}^{2} - 5y - y + 1 = - 4 {y}^{3} (y - 1) - 4 {y}^{2} (y - 1) + 5y(y - 1) - (y - 1) = \\ = - (y - 1)(4 {y}^{3} + 4 {y}^{2} - 5y + 1) = - (y - 1)(4 {y}^{3} - 2 {y}^{2} + 6 {y}^{2} - 3y - 2y + 1) = - (y - 1)(2 {y}^{2} (2y - 1) + 3y(2y - 1) - (2y - 1)) = - (y - 1)(2y - 1)(2 {y}^{2} + 3y - 1)$