Question

if A and B are the two vectors representing two diagonals of a parallelogram. what is the area of that parallelogram

Answer 1

One diagonal would be the vector sum of adjacent sides .... A=a+b
The other diagonal would be the vector difference between adjacent sides B=a-b
A+B = 2a .... a=(A+B)/2
A-B =2b .... b=(A-B)/2
a cross b = area