Bonjour,
Question 1 :
[tex]\overrightarrow{AM}(x - 2;y-1)[/tex]
[tex]det (\overrightarrow{AM};\overrightarrow{u}) = \left|\begin{array}{ccc}x-2 & 2\\y -1 & 3\end{array}\right|$ =(x-2) \times 3 -(y-1) \times 2 = 0[/tex]
[tex]= 3x - 6-2y + 2 = 0[/tex]
[tex]= 3x -2y -4 = 0[/tex]
Question 2 :
[tex]\overrightarrow{AM}(x - 3;y+2)[/tex]
[tex]det (\overrightarrow{AM};\overrightarrow{u}) = \left|\begin{array}{ccc}x-3 & \frac{1}{2} \\y +2 & -1\end{array}\right|$ =(x-3) \times (-1) -(y+2) \times \frac{1}{2} = 0[/tex]
[tex]= -x + 3 -\frac{1}{2}y- 1 = 0[/tex]
[tex]= -x - 0,5y + 2 = 0[/tex]
