Question

If two of the adjacent sides of a parallelogram are represented by vectors a 2i plus 3j minus k b I plus 2 j plus 4k

. The

area of the parallelogram will be

A) root 392 B) root 278 C) root 92 D) root 184​

Answer 1

Step-by-step explanation:

Correct option is

D

Area=

2

1

21

.

Let d

1

=a+b=i−3j+2k,d

2

=b+c=−i+2j

Now d

1

×d

2

=

∣

∣

∣

∣

∣

∣

∣

∣

i

1

−1

j

−3

2

k

2

0

∣

∣

∣

∣

∣

∣

∣

∣

=−4i−2j−k

Hence area of parallelogram is =

2

1

∣d

1

×d

2

∣=

2

1

21