sin β = 1/9
sec β = 1/cos β
[tex]cos \beta = \sqrt{1-( \frac{1}{9}) ^{2}} = \\ \sqrt{ \frac{80}{81} } = \\ \frac{4 \sqrt{5} }{9} [/tex]
[tex]sec \beta = \frac{1}{ \frac{4 \sqrt{5} }{9} } = \frac{9}{4 \sqrt{5} }= \frac{9 \sqrt{5} }{20} [/tex]
sec β = 1.00623
