Mohon bantuan nya ya soal tentang vektor setidak nya 2 soal....

nomor 15
a + b = [tex] \left[\begin{array}{ccc}1\\2\end{array}\right] + \left[\begin{array}{ccc}3\\1\end{array}\right] = \left[\begin{array}{ccc}4\\4\end{array}\right] [/tex]

nomor 16
a + b + c =[tex] \left[\begin{array}{ccc}1\\2\end{array}\right]+ \left[\begin{array}{ccc}3\\1\end{array}\right]+ \left[\begin{array}{ccc}1\\9\end{array}\right] = \left[\begin{array}{ccc}5\\12\end{array}\right] [/tex]
|a + b + c| = [tex] \sqrt{ 5^{2}+ 12^{2} } = 13[/tex]

nomor 17
5a + 2b - 3c = [tex]5 \left[\begin{array}{ccc}2\\-1\end{array}\right] +2 \left[\begin{array}{ccc}3\\2\end{array}\right] -3 \left[\begin{array}{ccc}4\\-5\end{array}\right]= \left[\begin{array}{ccc}10+6-12\\-5+4+15\end{array}\right] = \left[\begin{array}{ccc}4\\14\end{array}\right] [/tex]

nomor 18
p = AB = [tex] \left[\begin{array}{ccc}-2-3\\5-4\\-3-7\end{array}\right] = \left[\begin{array}{ccc}-5\\1\\-10\end{array}\right] [/tex]

q = BC = [tex] \left[\begin{array}{ccc}6-(-2)\\-3-5\\-5-(-3)\end{array}\right] = \left[\begin{array}{ccc}8\\-8\\-2\end{array}\right] [/tex]

p+q = [tex] \left[\begin{array}{ccc}5\\1\\-10\end{array}\right]+ \left[\begin{array}{ccc}8\\-8\\-2\end{array}\right] = \left[\begin{array}{ccc}13\\-7\\-12\end{array}\right] [/tex]

nomor 19
2a + b - c = [tex]2 \left[\begin{array}{ccc}1\\2\\3\end{array}\right] + \left[\begin{array}{ccc}-3\\-2\\-1\end{array}\right] - \left[\begin{array}{ccc}1\\-2\\3\end{array}\right] = \left[\begin{array}{ccc}2-3-1\\4-2+2\\6-1-3\end{array}\right] = \left[\begin{array}{ccc}-2\\4\\2\end{array}\right] [/tex]

nomor 20
3p - q + 2r = [tex]3 \left[\begin{array}{ccc}10\\-3\\0\end{array}\right] - \left[\begin{array}{ccc}3\\2\\-1\end{array}\right] + 2 \left[\begin{array}{ccc}0\\4\\7\end{array}\right] = \left[\begin{array}{ccc}30-3+0\\-9-2+8\\0+1+14\end{array}\right] = \left[\begin{array}{ccc}27\\-3\\15\end{array}\right] [/tex]