What is the correct way to calculate the volume of a tetrahedron?

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SUMMARY

The correct method to calculate the volume of a tetrahedron formed by points P1(2,-1,4), P2(-1,0,3), P3(4,3,1), and P4(3,-5,0) involves using the formula V = (1/6) * |A · (B × C)|, where A, B, and C are vectors derived from the points. The vectors were correctly identified as A = P1P2, B = P1P3, and C = P1P4. However, the calculated triple scalar product was incorrectly computed as 29; the correct value is 101, leading to the volume V = 101/6.

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Homework Statement


Given points P1(2,-1,4),P2(-1,0,3),P3(4,3,1),P4(3,-5,0)
determin the volume of the tetrahedron P1P2P3P4


Homework Equations


I believe the formula is (1/6)*the triple scalar product


The Attempt at a Solution



I found A=P1P2=(-3,1,-1)
B=P1P3=(2,4,-3)
C=P1P4=(1,-4,-4)
and the triple scalar product i found was:29 and for the volume:V=29/6

What am i doing wrong?The answer in the book is V=101/6
 
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Your A, B, and C vectors appear to be correct, but their triple product is 101, not 29. (The triple product is most easily computed as the determinant of the 3x3 matrix whose rows are A, B, and C.)
 

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