What is the area of the parallelogram whose sides are vectors `2overset^i+overset^j` and `2overset^j+overset^k` ?

Explanation

`overset^i+2overset^j+overset^k` are `2overset^i+3overset^j+alphaoverset^k` are perpendicular. `rArr(overset^i+2overset^j+overset^k)`.`(2overset^i+3overset^j+alphaoverset^k)=0rArr2+6+alpha=0rArralpha=-8`