Question

daca cosx = 5/13 calculati tgx x ( 0 , pi/2)

Answer 1

x fiind in cadranul I : sinx=$\sqrt{1-cos^2x}= \sqrt{1-( \frac{5}{13})^2 }= \sqrt{\frac{169-25}{169}}= \frac{12}{13}$, deci tgx=$\frac{sinx}{cosx}= \frac{ \frac{12}{13} }{ \frac{5}{13} }= \frac{12}{5}$