Question

Sin 17=x/y
Find sec17-sin73

Answer 1

cos17=
$\sqrt{ {y}^{2} - {x}^{2} }$
sec17=
$\frac{1}{ \sqrt{ {y}^{2} - {x}^{2} } }$
sin(90-17)=cos17

=
$\frac{1 - {x}^{2} + {y}^{2} }{ \sqrt{ {y}^{2} - {x}^{2} } }$