hờ..hờ...v...e...c...t...ơ.....
cho tam giác ABC. lấy M, N, P thỏa mãn:
$\ov
erright
arrow{MB
}=3
\ov
erright
arrow{MC
}$,
$\ov
erright
arrow{NA
}+3
\ov
erright
arrow{NC
}=
\ov
erright
arrow{0
}$,
$\ov
erright
arrow{PA
}+
\ov
erright
arrow{PB
}=
\ov
erright
arrow{0
}$. tìm
$\ov
erright
arrow{M
P}$,
$\ov
erright
arrow{MN
}$ theo
$\ov
erright
arrow{AB
}$,
$\ov
erright
arrow{AC
}$. suy ra M, N, P thẳng hàng
Vec-tơ
hờ..hờ...v...e...c...t...ơ.....
cho tam giác ABC. lấy M, N, P thỏa mãn: vtMB=3vtMC, vtNA+3vtNC=vt0, vtPA+vtPB=vt0. tìm vtM
B, vtMN theo vtAB,
vtAC. suy ra M, N, P thẳng hàng
Vec-tơ
hờ..hờ...v...e...c...t...ơ.....
cho tam giác ABC. lấy M, N, P thỏa mãn:
$\ov
erright
arrow{MB
}=3
\ov
erright
arrow{MC
}$,
$\ov
erright
arrow{NA
}+3
\ov
erright
arrow{NC
}=
\ov
erright
arrow{0
}$,
$\ov
erright
arrow{PA
}+
\ov
erright
arrow{PB
}=
\ov
erright
arrow{0
}$. tìm
$\ov
erright
arrow{M
P}$,
$\ov
erright
arrow{MN
}$ theo
$\ov
erright
arrow{AB
}$,
$\ov
erright
arrow{AC
}$. suy ra M, N, P thẳng hàng
Vec-tơ