Question

complete the following ​

Answer 1

$\frac{ \cos(54) }{ \sin(36) } - \frac{ \cos(54) }{ \cos(.) } \\ \frac{ \cos(54) }{ \sin(90 - 54) } - \frac{ \cos(54) }{ \sin(90 - 36) } \\ \frac{ \cos(54) }{ \cos(54) } - \frac{ \cos(54) }{ \cos(54) } \\ 0$