Question

if sin a = 3/5 find sec a​

Answer 1

Given

sinA = 3/5

Therefore

cosA =

$\sqrt{1 - {sina}^{2} }$

=

$= \sqrt{1 - {( \frac{3}{5}) }^{2} }$

$= \sqrt{1 - \frac{9}{25} }$

$= \sqrt{ \frac{25 - 9}{25} }$

$= \sqrt{ \frac{16}{25} }$

$= \frac{4}{5}$

Therefore

SecA = 1/CosA

$= \frac{1}{ \frac{4}{5} }$

$= \frac{5}{4}$