解ï¼ï¼2ï¼è§ä¸å¾ï¼ä½PFâ¥ADäºFï¼è¿ç»CFï¼ä½MEâ¥GFäºEï¼ä½CGâ¥ADäºGï¼è¿ç»PGï¼å¯ä»¥çåºï¼ABCD为æ£æ¹ä½AB=AP=PGï¼AF=FG=AB/2ï¼â³PGC为çè °ç´è§ä¸è§å½¢ï¼â³PAG为çè¾¹ä¸è§å½¢ï¼åï¼ PC=PB=â2AB; ä½PHâ¥BCäºHï¼PH=â(PC^2+HC^2)=â(2+1/4)AB=3AB/2;
å 为PM=PC/3ï¼æ以ï¼MC=(1-1/3)PC=2PC/3; Sâ³MBC=(1/2)BC*(2/3)PC=AB^2/2=2â7/3;
AB^2=4â7/3ï¼AB=â(4â7/3)=2â(â7/3); PF=â(PG^2-FG^2)=â3AB/2ï¼
Vp-ABCD=(1/3)[(BC+AD)*AB/2]*PF=(1/3)*(1/2)*(3AB^3)*(â3/2)=(â3/4)*(4â7/3)*(2â(â7/3)
=2â(7â7)/3ã