做辅助线CD⊥AB,交AB延长线与D,则∠ACD=45°,|BD|:|CD|=1:2
|AD|=|CD|=|AC|*sin45°=2*2^0.5/2=2^0.5 (根号2)
|BD|=1/2|CD|=2^0.5/2
|AB|=|AD|-|BD|=2^0.5-2^0.5/2=2^0.5/2≈0.71(米)
做辅助线CD⊥AB,交AB延长线与D,则∠ACD=45°,|BD|:|CD|=1:2
|AD|=|CD|=|AC|*sin45°=2*2^0.5/2=2^0.5 (根号2)
|BD|=1/2|CD|=2^0.5/2
|AB|=|AD|-|BD|=2^0.5-2^0.5/2=2^0.5/2≈0.71(米)