Question 1156911
{{{(sin^4(x)-cos^4(x))/(sin^""(x)cos^""(x))=tan^""(x)-cot^""(x)}}}
<pre>
Work with the left sides:

{{{(sin^4(x)-cos^4(x))/(sin^""(x)cos^""(x))}}}

{{{((sin^2(x)-cos^2(x)^"")(sin^2(x)+cos^2(x)^""))/(sin^""(x)^""cos^""(x))}}}

{{{((sin^2(x)-cos^2(x)^"")(1^""))/(sin^""(x)^""cos^""(x))}}}

{{{(sin^2(x)-cos^2(x)^"")/(sin^""(x)^""cos^""(x))}}}

{{{matrix(1,3, ( sin^2(x) )/( sin^""(x)^""cos^""(x) ),""-"",( cos^2(x) )/( sin^""(x)^""cos^""(x) ))   }}}

{{{matrix(1,3, ( sin^cross(2)(x) )/( cross(sin^""(x)^"")cos^""(x) ),""-"",( cos^cross(2)(x) )/( sin^""(x)^""cross(cos^""(x)) ))   }}}

{{{matrix(1,3, ( sin^""(x) )/(cos^""(x) ),""-"",( cos^""(x) )/( sin^""(x) ))   }}}

{{{matrix(1,3, tan^""(x) ,""-"", cot^""(x) )   }}}

Edwin</pre>