Question

identidades trigonométricas

Answer 1

${cosx.secx+ctg^2x=}\\\\{\frac{cosx}{1}\times\frac{1}{cosx}+\frac{cos^2x}{sen^2x}=}\\\\{1+\frac{cos^2x}{sen^2x}=}\\\\{\frac{sen^2x+cos^2x}{sen^2x}=}\\\\{\frac{1}{sen^2x}=}\\\\{\boxed{csc^2x}}\\\\{\mathbf{salu2.!!\ :)}}\\{\mathbf{Wellington}}$