Question

Given : $secA=\frac{29}{21}$, evaluate : $sinA-\frac{1}{tanA}$ is $-\frac{m}{580}$, m is

• A. 130
• B. 215
• C. 209
• D. 524

Answer 1

The correct option is C 209

$\sec A=\frac{29}{21}$
$\sec A=\frac{H}{B}=\frac{29}{21}$
Using Pythagoras Theorem,
$H^2=P^2+B^2$
${29}^2=P^2+{21}^2$
$841=441+P^2$P = 20$Now,$\sin A - \frac{1}{\tan A} = \sin A - \cot A$=$\frac{P}{H} - \frac{B}{P}$=$\frac{20}{29} - \frac{21}{20}$=$\frac{400 - 609}{580}$=$\frac{- 209}{580}$