Question 175834
You need to use the trig identity
{{{(sec(x))^2 = 1+(tan(x))^2}}}
So  then
{{{(sec(x))^2+(tan(x))^2=3}}} can be rewritten as
{{{1+(tan(x))^2+(tan(x))^2=3}}}
{{{1+2(tan(x))^2=3}}}
{{{(tan(x))^2=1}}}
{{{tan(x)=1}}} and {{{tan(x)=-1}}}
All that's left is to use a trig table to determine the angles at which the tangent is 1 or -1.