证明 3 x 0.333... = 0.999...
等同于证明:0.333...+0.333...+0.333...=0.999...
等同于证明:0.111...+0.111... = 0.222...
难道这还要证明吗?
等同于证明:0.333...+0.333...+0.333...=0.999...
等同于证明:0.111...+0.111... = 0.222...
难道这还要证明吗?