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Given the module of vector a = 3, B = 4, C = 4, and the vector a + B + C is 0. Find AB + CB + AC
|a|=3,|b|=4,|c|=4
a+b+c=0
To find :a.b+b.c+c.a
a+b+c=0
(a+b+c).(a+b+c)=0
|a|^2+|b|^2+|c|^2 + 2(a.b+b.c+c.a)=0
9+16+16+2(a.b+b.c+c.a)=0
(a.b+b.c+c.a)=-41/2
As shown in the figure, on the number axis, points a, B and C represent 4, 8 and - 3 respectively. Find the lengths of AB, AC and CB
From the meaning of the title
AC=4-（-3）=7
AB=8-4=4
BC=8-（-3）=11
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