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Check that the four points P(2,4,4)P(2,4,4), Q(3,1,6)Q(3,1,6), R(2,8,0)R(2,8,0), and S(5,2,3)S(5,2,3) all lie in a plane

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Q. Check that the four points P(2,4,4)P(2,4,4), Q(3,1,6)Q(3,1,6), R(2,8,0)R(2,8,0), and S(5,2,3)S(5,2,3) all lie in a plane
  1. Calculate Vectors: Find the vectors PQPQ, PRPR, and PSPS using the coordinates of the points.\newlinePQ=QP=(32,14,64)=(1,3,2)PQ = Q - P = (3 - 2, 1 - 4, 6 - 4) = (1, -3, 2)\newlinePR=RP=(22,84,04)=(0,4,4)PR = R - P = (2 - 2, 8 - 4, 0 - 4) = (0, 4, -4)\newlinePS=SP=(52,24,34)=(3,2,1)PS = S - P = (5 - 2, 2 - 4, 3 - 4) = (3, -2, -1)
  2. Check Coplanarity: Check if the vectors PQ, PR, and PS are coplanar by finding the scalar triple product.\newlineThe scalar triple product of vectors aa, bb, and cc is given by [abc]=a(b×c)[a b c] = a \cdot (b \times c).\newlineFirst, calculate the cross product of PR and PS.\newlinePR \times PS = \left| \begin{array}{ccc}\(\newlinei & j & k (\newline\)0 & 4 & -4 (\newline\)3 & -2 & -1 (\newline\)\end{array} \right|\)\newline=(41(4)2)i(01(4)3)j+(0243)k= (4 \cdot -1 - (-4) \cdot -2)i - (0 \cdot -1 - (-4) \cdot 3)j + (0 \cdot -2 - 4 \cdot 3)k\newline=(48)i(0+12)j+(012)k= (-4 - 8)i - (0 + 12)j + (0 - 12)k\newline=(12)i(12)j(12)k= (-12)i - (12)j - (12)k\newline=(12,12,12)= (-12, -12, -12)
  3. Calculate Dot Product: Now, calculate the dot product of PQPQ and the cross product of PRPR and PSPS.PQ(PR×PS)=(1,3,2)(12,12,12)PQ \cdot (PR \times PS) = (1, -3, 2) \cdot (-12, -12, -12)= 1(12)+(3)(12)+2(12)1*(-12) + (-3)*(-12) + 2*(-12)= 12+3624-12 + 36 - 24= 00

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