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44.   The two adjacent sides of a parallelogram are  2 i ^   -   4 j ^   -   5 k ^   a n d   2 i ^   +   2 j ^   +   3 k ^ . Find the two unit vectors parallel to its diagonals. Using the diagonal vectors, find the area of the parallelogram.

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Note:P=a+b=2i-4j-5k+2i+2j+3k=4i-2j-2kand P'=b-a=2i+2j+3k-2i+4j+5k=6j+8kNow, P×P'=ijk4-2-2068=i-16+12-j32+k24=-4i-32j+24kNow, P×P'=-42+-322+242=16+1024+576=1616=4101 
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