What do "$\Sigma$" and "$\Pi$" mean in trigonometry? (Eg, $\Pi \sin \left( A - \frac{\pi}{4} \right)$ and $\Sigma \tan A$)

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I came across this question and I have never seen these symbols used as they are here. If somebody could please explain to me what they mean that would be great.

If $A, B, C$ are the angles of a triangle $ABC$ and $\Pi \sin \left( A - \frac{\pi}{4} \right) = \frac{1}{2\sqrt{2}}$ then $\Sigma \tan A \tan B $ will not be equal to:
(A) $\Sigma \tan A$
(B) $\Sigma \cot A$
(C) $\left( \Sigma \tan A \right)^{-1}$
(D) $\left( \Sigma \cot A\right)^{-1}$

The symbols in question are the $\Sigma$ and $\Pi$ symbols. They usually represent the sum or product of a series but have values like $\sum_{i = 1}^{5}$ and the variable $i$ would then be incremented. These symbols don't have any limits nor incrementing variables. I couldn't find anything on Google about this.

Again, I only need to know what the symbols mean. You don't have to solve the question.

Thanks!

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The symbols $\Sigma$ and $\Pi$ are not specific to trigonometry.

As you indicated, they mean sum and product, respectively.

In this situation, they indicate a sum or product over all the angles of the triangle $ABC$.

E.g., $\sum \tan A=\tan A +\tan B+\tan C$; $\sum A=180^o$.