在平面几何里,有勾股定理:“设△ABC的两边AB,AC互相垂直,则AB2+A

在平面几何里,有勾股定理:“设△ABC的两边ABAC互相垂直,则AB2+AC2=BC2”拓展到空间,类比平面几何的勾股定理,“设三棱锥ABCD的三个侧面ABCACD、ADB 两两相互垂直,则可得” (    )

AAB2+AC2+ AD2=BC2+ CD2 + BD2        B 

C  DAB2×AC2×AD2=BC2 ×CD2 ×BD2

答案

B

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