Utilisez la "formule de Gregory･Leibniz" pour trouver la valeur approximative de pi.
Use the following "Gregory･Leibniz's Formula" to find the approximate value of pi.
π = 4(1 - 1/3 + 1/5 - 1/7 + 1/9 - ･･･)
Let's observe how the approximate value of pi can be obtained as the number of terms increases.