If OACB is a parallelogram with `vecOC=veca` and `vecAB=vecb`, then `vecOA` is equal to

If |veca|=2,|vecb|=3 and veca.vecb=4 , then |veca-vecb| is equal to

If veca and vecb are vectors such that |veca|=2,|vecb|=3 and veca*vecb=4 , then |veca-vecb| is equal to :

|vecA xx vecB|^2 + |vecA . vecB|^2 is equal to

If |veca|=|vecb| , then (veca+vecb).(veca-vecb) is equal to

If |veca|=|vecb| , then (veca+vecb).(veca-vecb) is equal to

One of the diagonals of parallelogram ABCD with veca and vecb as adjacent sides is veca+vecb . The other diagonal vec(BD) is