The volume of tetrahedron whose vertices are
A = (3, 2, 1) ,~B = (1, 2, 4),~ C = (4, 0, 3),~ D = (1, 1, 7)~will be –––––cubic units
56
Given vertices are→A=(3,2,1)→B=(1,2,4)→C=(4,0,3)→D=(1,1,7)So the three coterminous edges we can form are →AB,→AC and →ADRight?So →AB=((1−3),(2−2),(4−1))=(−2,0,3)So →AC=((4−3),(0−2),(3−1))=(1,−2,2)So →AD=((1−3),(1−2),(7−1))=(−2,−1,6)So volume=16∣∣[→AB →AC →AD]∣∣Remember that we hav eto take the absolute value of scalar triple product.So[→AB →AC →AD]=∣∣ ∣∣−2031−22−2−16∣∣ ∣∣=20−15=5So volume of tetrahedron=16[→AB →AC →AD]=16×5=56cubic units.