3х^2+8х+2=0; делим на 3;
х^2+2*4/3х+16/9-16/9+2/3=0;
(х+4/3)^2=16/9-6/9=10/9;
х+4/3=+-(10^1/2)/3; х=-4/3+-(10^1/2)/3;
х1=(-4-10^1/2)/3; х2=(-4+10^1/2)/3.
3Sin( - 3П/2) = - 3Sin3П/2 = - 3 * (- 1) = 3
номально пиши.................................
5 задача
1. 8+6+12=26 часов=1день 2часа
(5^{2n+2)*2^{2n+2)=10^{2n+2}/2010^{2n} = 1000^{2n}/2010^{2n} = -1010^{2n}