Question 1131256
Verify the identity

{{{ (csc^4(x)-1)/(cot^2(x)) = 2 + cot^2(x) }}}
{{{ csc^4(x)-1 = 2cot^2(x) + cot^4(x) }}}
{{{1 - sin^4(x) = 2sin^2(x)cos^2(x) + cos^4(x)}}}

{{{1 = sin^4(x) + 2sin^2(x)cos^2(x) + cos^4(x)}}}

{{{1 = (sin^2(x) + cos^2(x))^2}}}
1 = 1^2
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I'm still waiting for an example where working only one side makes a difference.