Hello young mathematicians! Today we're going on an exciting adventure to discover how to find the area of a circle. Look at this beautiful circle with radius r. Can you guess how much space is inside it? Let's find out together!
好主意！让我们把圆切成相等的小块，就像切美味的披萨一样。看看我们如何把它分成8个相等的部分。每一片都从中心延伸到边缘。你能数出所有这些彩色的小块吗？