13sin469градусов-8cos341 градусов/cos 19 градусов= ?

Решите задачу:

$\frac{13 \sin469^{o}-8 \cos341^{o}}{cos19^{o}}=\frac{13 \sin(360^{o}+109^{o})-8 \cos(360^{o}-19^{o})}{cos19^{o}}=\\ \\ =\frac{13 \sin109^{o}-(-8 \cos19^{o})}{cos19^{o}} = \frac{13 \sin(90^{o}+19^{o})+8 \cos19^{o}}{cos19^{o}} = \\ \\=\frac{13 \cos19^{o}+8 \cos19^{o}}{cos19^{o}} = \frac{21 \cos19^{o}}{cos19^{o}} = 21$