70,2,90,7,100,70,1,300,3,600,60,6
84!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-|х|=-2 /:(-1)
|х|=2
х=2 х=-2
Ответ {-2; 2}
1) 20/7 x^3+12x^2-2/3x^2
2)7/2корень(х)-3sin6x+3/cos^2(x)
3)(5x-3)/2корень(х)+5корень(х)
4)(-3x^2-6-6x^2)/(x^2+2)^2=(-9x^2-6)/(x^2+2)^2