<span>А -0.9
проверим
</span>
-0.3*<span>-0.9+1.8=2,07
</span>2,07<span>>2</span>
5x³ - 125x = 0;
5x(x² - 25) = 0;
x(x - 5)(x + 5) = 0;
<span>x = {-5; 0; 5}.</span>
(√2сosa-2cosπ/4cosa-2sinπ/4sina)/(2sinπ/6cosa+2cosπ/6sina-√3sina)=
=(√2cosa-2*√2/2*cosa-2*√2/2*sina)/(2*1/2*cosa+2*√3/2sina-√3sina)=
=(√2cosa-√2cosa-√2sina)/(cosa+√3sina-√3sina)=-√2sina/cosa=-√2tga
Мой ответ::::::::::::
1)-2;10
7)-23;1