Question

sendo cos x= 3/5 e x um arco do 2 quadrante, calcule a cossec x.

Answer 1

$\mathsf{cos^{2}(x)={(\dfrac{3}{5})}^{2}=\dfrac{9}{25}}$

$\mathsf{\dfrac{25-9}{25}=\dfrac{16}{25}}$

$\mathsf{sen^{2}(x)=\dfrac{16}{25}}\\\mathsf{sen(x)=\sqrt{\dfrac{16}{25}}}\\\mathsf{sen(x)=\dfrac{4}{5}}$

$\mathsf{cosec(x)=\dfrac{1}{sen(x)}=\dfrac{5}{4}}$