Sin^3x+7sinxcos^2x+6cos^3x

sin³x-7sinxcos²x+6cos³x=0 (cos³x≠0) tg³x-7tgx+6=0 tgx=y y³-7y+6=0 (y-1)(y-2)(y+3)=0 y₁=1;y₂=2;y₃=-3 1) tgx=1;x=π/4+πn,n∈Z 2) tgx=2;x=arctg2+πk,k∈Z 3) tgx=-3;x=-arctg3+πm,m∈Z