
Because which numbers will make the expessions undefined. We will focus on the denominator only.
Factor the terms.

Now which 2 numbers that will make these terms become 0?
12 and - 1 of course.
So these 2 numbers that will make the expressions undefined are 12 and - 1
<em><u>There is no solution!</u></em>
Edited : I apologise I misunderstood the question.
You can solve the equation.
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<h3>E
xplanation:</h3>
Replace cos^2(θ) with 1-sin^2(θ), and cot(θ) with cos(θ)/sin(θ).
cos^2(θ)cot^2(θ) = cot^2(θ) - cos^2(θ)
(1 -sin^2(θ))cot^2(θ) = . . . . . replace cos^2 with 1-sin^2
cot^2(θ) -sin^2(θ)·cos^2(θ)/sin^2(θ) = . . . . . replace cot with cos/sin
cot^2(θ) -cos^2(θ) = cot^2(θ) -cos^2(θ) . . . as desired