Помогите. Алгебра 10. Тригонометрия

1 2sin²x(3ππ/2+x)=cosx 2cos²x-cosx=0 cosx(2cosx-1)=0 cosx=0⇒x=π/2+πn,n∈z -3π/2≤π/2+πn≤0 -3≤1+2n≤0 -4≤2n≤-1 -2≤n≤-1/2 n=-2⇒x=π/2-2π=-3π/2 n=-1⇒x=π/2-π=-π/2 2cosx-1=0 cosx=1/2⇒x=+-π/3+2πn,n∈z -3π/2≤-π/3+2πn≤0 -9≤-2+12n≤0 -7≤12n≤2 -7/12≤n≤2/12 n=0⇒x=-π/3 -3π/2≤π/3+2πn≤0 -9≤2+12n≤0 -11≤12n≤-2 -11/12≤n≤-2/12 нет решения 2 tg³x+tg²x-3tgx-3=0 tg²(tgx+1)-3(tgx+1)=0 (tgx+1)(tgx-√3)(tgx+√3)=0 tgx+1=0⇒tgx=-1⇒x=-π/4+πn,n∈z 2π≤-π/4+πn≤7π/2 8≤-1+4n≤14 9≤4n≤15 9/4≤n≤15/4 n=3⇒x=-π/4+3π=11π/4 tgx-√3=0⇒tgx=√3⇒x=π/3+πn,n∈z 2π≤π/3+πn≤7π/2 12≤2+6n≤21 10≤6n≤19 10/6≤n≤19/6 n=2⇒x=π/3+2π=7π/3 n=3⇒x=π/3+3π=10π/3 tgx+√3=0⇒tgx=-√3⇒x=-π/3+πn,n∈z 2π≤-π/3+πn≤7π/2 12≤-2+6n≤21 14≤6n≤23 14/6≤n≤23/6 n=3⇒x=-π/3+3π=8π/3