X+21 =Y −3−2 =Z −1−2 ⇒D(T −2;−2T+3;−2T+1)SABCD=3√2⇒SACD=3√20,5

2. - DE THI THU DAI HOC 2013
DE THI THU DAI HOC 2013
2. (1,0 điểm)+) D∈d:x+21 =y −3−2 =z −1−2 ⇒D(t −2;−2t+3;−2t+1)S

ABCD

=3

√

2⇒S

ACD

=3

√

20,5