求D1-AEF体积可换底,即求F-AED1的体积F到AED1的高为a,S△AED1=1/2*(a/2)*a=a^2/4则体积为:V=1/3Sh=1/3*a^2/4*a=a^3/12易知AE=AF,EF平移即为ABCD对角线,则EF=√2aAE=√5a/2则△AEF的高h=√3a/2则S△AEF=1/2*√2a*√3a/2=√6a^2/4V=1/3S△AED1*h=1/3S△AEF*h=a^3/12则D1到AEF的距离为h=√6a/2