圓心 \(\displaystyle{C\left( h,k \right) }\):
半徑 \(\displaystyle{ r = }\)
點 \(\displaystyle{ Q\left( {{x}_{0}},{{y}_{0}} \right) }\):
線段 \(\displaystyle{ CQ }\):
\(\displaystyle{{{x}_{0}}^{2}+{{y}_{0}}^{2}+D{{x}_{0}}+E{{y}_{0}}+F}\)
0
結論: