If the vectors `hat(i)-3hat(j)+2hat(k), -hat(i)+2hat(j)` represent the diagonals of a parallelogram, then its area will be
If the vectors `hat(i)-3hat(j)+2hat(k), -hat(i)+2hat(j)` represent the diagonals of a parallelogram, then its area will be
A. `sqrt(21)`
B. `sqrt(21)/2`
C. `2sqrt(21)`
D. `sqrt(21)/4`
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Correct Answer - C
Let `a=hati-3hatj+2hatk, b=-hati+2hatj`
Now, `axxb=|{:(hati,hatj,hatk),(1,-3,2),(-1,2,0):}|=-4hati-2hatj-hatk`
`:." "` Area of parallelogram `=1/2|axxb|=1/2sqrt(16+4+1)=sqrt(21)/2`
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