Question

If $\tan A=\frac{5}{12}$, then $\sin A$ is :

• A. $\frac{5}{13}$
• B. $\frac{12}{13}$
• C. $\frac{13}{5}$
• D. $\frac{13}{12}$

Answer 1

The correct option is A $\frac{5}{13}$

Given, $\tan A=\frac{5}{12}=\frac{p}{b}=\frac{BC}{AB}$

$\therefore h=AC=\sqrt{5^2+{\left(12\right)}^2}=\sqrt{25+144}$$=\sqrt{169}=13$

$\sin A=\frac{BC}{AC}=\frac{p}{h}=\frac{5}{13}$