6.
如图,用下面的方法可以画出\(\triangle AOB\)的“内接等边三角形”,阅读后证明相应的问题.
画法:
\(①\)在\(\triangle AOB\)内画等边\(\triangle CDE\),使点\(C\)在\(OA\)上,点\(D\)在\(OB\)上;
\(②\)连接\(OE\)并延长,交\(AB\)于点\(E′\),过点\(E′\)作\(E′C′/\!/EC\),交\(OA\)于点\(C′\),作\(E′D′/\!/ED\),交\(OB\)于点\(D′\);
\(③\)连接\(C′D′\),则\(\triangle C′D′E′\)是\(\triangle AOB\)的内接三角形.
请判断\(\triangle C′D′E′\)是否是等边三角形,并说明理由.