Разложите на множители многочлен:
1) $x^2 - 4x + 3$;
2) $a^2 + 2a - 24$;
3) $y^2 + 12y + 35$;
4) $x^2 + x - 6$;
5) $c^2 + 8cd + 15d^2$;
6) $9x^2 - 30xy + 16y^2$.
$x^2 - 4x + 3 = x^2 - 4x + 4 - 1 = (x^2 - 4x + 4) - 1 = (x - 2)^2 - 1 = (x - 2 - 1)(x - 2 + 1) = (x - 3)(x - 1)$
$a^2 + 2a - 24 = a^2 + 2a - 25 + 1 = (a^2 + 2a + 1) - 25 = (a + 1)^2 - 5^2 = (a + 1 - 5)(a + 1 + 5) = (a - 4)(a + 6)$
$y^2 + 12y + 35 = y^2 + 12y + 36 - 1 = (y^2 + 12y + 36) - 1 = (y + 6)^2 - 1 = (y + 6 - 1)(y + 6 + 1) = (y + 5)(y + 7)$
$x^2 + x - 6 = x^2 + x - 6,25 + 0,25 = (x^2 + x + 0,25) - 6,25 = (x + 0,5)^2 - 2,5^2 = (x + 0,5 - 2,5)(x + 0,5 + 2,5) = (x - 2)(x + 3)$
$c^2 + 8cd + 15d^2 = c^2 + 8cd + 16d^2 - d^2 = (c^2 + 8cd + 16d^2) - d^2 = (c + 4d)^2 - d^2 = (c + 4d - d)(c + 4d + d) = (c + 3d)(c + 5d)$
$9x^2 - 30xy + 16y^2 = 9x^2 - 30xy + 25y^2 - 9y^2 = (9x^2 - 30xy + 25y^2) - 9y^2 = (3x - 5y)^2 - (3y)^2 = (3x - 5y - 3y)(3x - 5y + 3y) = (3x - 8y )(3x - 2y)$
Пожауйста, оцените решение