Решить! 1. sin6x*ctg4x*tg3x=0 2. sin^2(x)+5sin(x)*cos(x)+4cos^2(x)=0 3. 4sin^2(2x)-2,5sin(4x)+7cos^2(2x)=3 4. 2tg^2(x)-tg(x)=1

1)sin6x=0⇒6x=πn, x=πn/6
ctg4x=0⇒4x=π/2+πn, x=π/8+πn/4
tg3x=0⇒3x=πn, x=πn/3
           x=πn/6 U   x=π/8+πn/4
2)Поделим на cos²x≠0
tg²x+5tgx+4=0
a=tgx , a²+5a+4=0, a1+a2=-5 U a1*a2=4⇒
a1=-4, tgx=-4,x=-arctg4+πn
a2=-1, tgx=-1, x= -π/2+πn
3)4sin²2x-5sin2xcos2x+7cos²2x-3sin²2x-3cos²2x=0
sin²2x-5sin2xcos2x+4cos²2x=0
Поделим на cos²x≠0
tg²2x-5tg2x+4=0
a=tg2x, a²-5a+4=0, a1+a2=5 U a1*a2=4⇒
a1=4, tg2x=4,2x=arctg4+πn, x=1/2arctg4+πn/2
a2=1, tg2x=1, 2x=π/2+ππn, x=π/4+πn/2
4)a=tgx, 2a²-a-1=0, D=9
a1=1, tgx=1,x=π/2+πn
a2=-1/2,tgx=-1/2,x= -arctg1/2+πn