Question

Д)$4 x^{2} -12x+9 textgreater 0;$
Е)$25 x^{2} +30x+9 textless 0;$
Ж)$-10 x^{2} +9x textgreater 0;$
З)$-2 x^{2} +7x textless 0;$

Answer 1

$4x^{2}-12x+9textgreater0,\ (2x)^2-2cdot2xcdot3+3^2 textgreater 0, \ (2x-3)^2 textgreater 0, \ 2x-3neq0, \ xneq1,5;$

$25x^{2}+30x+9textless0, \ (5x)^{2}+2cdot5xcdot3+3^2textless0, \ (5x+3)^2textless0, \ xinvarnothing;$

$-10x^{2}+9xtextgreater0, \ -10x(x-0,9)textgreater0, \ x(x-0,9)textless0, \ 0textless xtextless0,9, \ xin(0;0,9);$

$-2x^2+7x textless 0, \ -2x(x-3,5) textless 0, \ x(x-3,5) textgreater 0, \ left [ {{x textless 0,} atop {x textgreater 3,5;}} right. \ xin(-infty;0)cup(3,5;+infty).$

Answer 2

а под "з"?