Question

Помогите решить уравнения

Answer 1

$frac{6-7cosx+ cos^{2} x }{ cos^{2}x } = 0; 6-7cosx + cos^{2}x =0;$

$cos^{2} x-7c0sx +6 =0; cosx=a; a^{2} -7a+6 =0; a_{1} =1; a_{2} =6;$$cosx =1; x = 2 pi n, n∈Z; cosx =6; x = ∅;$