Răspuns:
)
AB= 4I+3J
AC= 1i+2j
Fie M - mijlocul lui BC
AB + AC = 2AM
AM(vector) = 5/2i + 5/2j =2,5i + 2,5j
AM= √(2.5)²+(2.5)²=√6.25+6.25 =√12.5
b) BG = 2/3 * BP
=> BP = 3/2 BG (1)
BP = (AB + BC )÷2 = (AB + BA + AC ) ÷2
=> BP = AC÷2 (2)
din (1) si (2) => 3/2 BG = AC/2
=> BG = AC/3
BG(vector) = 1/2 i + j
BG = √(1/4 + 1 ) = √5 /
