Решите 6sinx^2-4sin2x=-1
6sin²x-8sinxcosx+sin²x+cos²x=0/cos²x 7tg²x-8tgx+1=0 tgx=a 7a²-8a+1=0 D=64-28=36 a1=(8-6)/14=1/7⇒tgx=1/7⇒x=arctg1/7+πn,n∈z a2=(8+6)/14=1⇒tgx=1⇒x=π/4+πk,k∈z