Ответ:3*5*43*44*49-416+18=1390620-416+18=1390222
sina=V(1-cos^2a)=V(1-1/9)=V(8/9)=2V2/3
<span> (0,3x+4y)^2=0.09x^2+2.4xy+16y^2</span>