[tex]tg\alpha=\sqrt5\\\\\frac{sin\alpha}{cos\alpha}=\sqrt5\\\\sin\alpha=\sqrt5cos\alpha\\\\sin\alpha=\frac{2}{3}\sqrt5\\\\[/tex]
[tex]sin^2\alpha+cos^2\alpha=1\\\\(\frac{2}{3}\sqrt5)^2+(\frac{2}{3})^2=1\\\\\frac{20}{9}+\frac{4}{9}=1\\\\\frac{24}{9}=1[/tex]
Rowność falszywa.
Taki kąt nie istnieje