Question 1020189
By definition,
{{{sec^2(x)-1=tan^2(x)=sin^2(x)/cos^2(x)}}}
So,
{{{(sec^2(x)-1)/tan^2(x)=(sin^2(x)/cos^2(x))/sin^2(x)}}}
{{{(sec^2(x)-1)/tan^2(x)=1/cos^2(x))}}}
{{{(sec^2(x)-1)/tan^2(x)=sec^2(x)}}}