[tex]tan^{2}\theta - sin^{2}\theta = tan^{2}\theta sin^{2}\theta} \\
\frac{sin^{2}\theta}{cos^{2}\theta} - sin^{2}\theta =tan^{2}\theta sin^{2}\theta\\
\frac{sin^{2}\theta - sin^{2}\theta cos^{2}\theta}{cos^{2}\theta} =tan^{2}\theta sin^{2}\theta} \\
\frac{sin^{2}\theta(1 - cos^{2}\theta)}{cos^{2}\theta} =tan^{2}\theta sin^{2}\theta \\
\frac{sin^{2}\theta(sin^{2}\theta)}{cos^{2}\theta} =tan^{2}\theta sin^{2}\theta \\
tan^{2}\theta sin^{2}\theta = tan^{2}\theta sin^{2}\theta \\[/tex]