12, easy to know k=√3, let An- 1(xn- 1 0), an (xn, 0), Pn(x, √3/x). According to the relationship between the vertical line and the side length of an equilateral triangle, the side length of the nth triangle is 2/x Xn 2-xn-12 = 4, xn-12-xn-2 2 = 4, ... x22-x12.
Mathematical thinking method comes from mathematical cognitive activities, which in turn plays an important guiding role in mathematical