dluzsze o katach

[Siaraa]

sprawdź tożsamość tg \(\displaystyle{ ^{2} \alpha \cdot cos \alpha = \frac{1}{cos \alpha } -cos \alpha}\)

[Vax]

\(\displaystyle{ L = \tg^2 \alpha \cdot \cos \alpha = \frac{\sin^2\alpha}{cos^2\alpha} \cdot \cos \alpha = \frac{\sin^2\alpha}{\cos\alpha} = \frac{1-\cos^2\alpha}{\cos\alpha} = \frac{1}{\cos\alpha}-\cos\alpha = P}\)

Pozdrawiam.