Tìm x

----- Nội dung ảnh -----
b) \(\left(1 - \frac{1}{21}\right) x \left(1 - \frac{1}{22}\right) x \left(1 - \frac{1}{23}\right) \ldots x \left(1 - \frac{1}{1999}\right) x \left(1 - \frac{1}{2000}\right)\)