найдите значение выражения
4-7x^2 9x^2
------- - ------- при x=-3\4
2-x 2-x
(4-7x^2)-(9x^2) 4-7x^2-9x^2 4-16x^2
------------------ = ------------- = ----------
2-x 2-x 2-x
4+16(0.75)^2 4+16*0.5625 4+9 13
---------------- = -------------- = ------ = ------ = 10.4
2-0.75 1.25 1.25 1.25