Помогииииитеее 6cos2x + 8 sin^2x - 5 = 0 4 cos 2x + 10 cos x + 7 =0 3 sin 2x + 56 sin ^2x - 20 =0

6(1-2sin²x)+8sinx-5=0 -12sin²x+8sinx+1=0 12sin²x-8sinx-1=0 sinx=t   |t|≤1 12t²-8t-1=0 D=16+12=28 t=4+√28/12=4+2√7/12=2+√7/6 t=4-√28/12=2-√7/6 sinx=2-√7/6 x=[latex](-1)^n[/latex]arcsin(2-√7/6)+πn sinx=2+√7/6 x=[latex](-1)^n[/latex]arcsin(2+√7/6)+πn 4(2cos²x-1)+10cosx+7=0 8cos²x-4+10cosx+7=0 8cos²x+10cosx+3=0 cosx=t  |t|≤0 8t²+10t+3=0 D=25-24=1 t1=-5+1/8=-1/2 t2=-5-1/8=-3/4 cosx=-1/2 x=+-2π/3+2πn cosx=-3/4 x=+-arccos(-3/4)+2πn 3sin2x+56sin²x-20=0 6sinx*cosx+56sin²x-20sin²x-20cos²x=0 36sin²x+6sinx*cosx-20cos²x=0 поделим на cos²x≠0 36tg²x+6tgx-20=0 tgx=t 18t²+3t-10=0 D=9+4*10*18=729=27² t1=-3-27/18=-30/18=-5/3 t2=-3+27/18=24/18=4/3 tgx=-5/3 x=-arctg5/3+πn tgx=4/3 x=arctg4/3+πn