Тригонометрия,помогите,с решением,если можно

3 четверть => [email protected] отрицательный, [email protected] положительный
cos^[email protected] = 1 - sin^[email protected] = 1 - 144/169 = 25/169 => [email protected] = -5/13
[email protected] = [email protected]/[email protected] = (-12)/13 / (-5)/13 = 12/5 = 2,4.
[email protected] = -5/13
[email protected] = 2,4.