From the two identities above, the following table can be extrapolated. Note however that these conversion equations may not provide the correct sign (+ or −). For example, if sin θ = 1/2, the conversion in the table indicates that formula_1, though it is possible that formula_2. More information would be needed about which quadrant θ lies in to determine a single, exact answer.
मौलिक सम्बन्ध
ऐतिहासिक पृष्टभूमि
आवर्तता (periodicity)
टोलेमी का प्रमेय (Ptolemy's theorem)