If the position vectors of the vertices of a triangle are →A=^i+2^j+2^k,→B=2^i+3^j+^k,→C=3^i+^j−2^k ; Check whether the triangle is equilateral or not.
Open in App
Solution
→A=^i+^2j+^2k
→B=^2i+3^j+^k
→C=^3i+^j−^2k
→AB=^i+^j−^k=√12+12+(−1)2=√3
→BC=^i−2^j−3^k=√12+(−2)2+(−3)2=√14
→CA=2^i−1^j−4^k=√22+(−1)2+(−4)2=√21
Lengths of sides of this triangle are not equal.
Hence this triangle is not an equilateral triangle.