Объяснение:

у(1)= 1²+7×1-18= 1+7-18= -10

у(-1)= (-1)²+7×(-1)-18= 1-7-18= -6-18= -24

Ответ:

[tex]1)y = 1 = > x {}^{2} + 7x - 18 = 1 \\ x {}^{2} + 7x - 19 = 0 \\ d = 49 + 4 \times 19 = 125 \\ x1 = \frac{ - 7 + 5 \sqrt{5} }{2} \\ x2 = \frac{ - 7 - 5 \sqrt{5} }{2 } \\ \\ 2)y = - 1 = > x {}^{2} + 7x - 18 = - 1 \\ x { }^{2} + 7x - 17 = 0 \\ d = 49 + 4 \times 18 = 121 \\ x1 = \frac{ - 7 + 11}{2} = 2 \\ x2 = \frac{ - 7 - 11}{2} = - 9[/tex]