Question

Two vectors A and B have magnitude a=3=b, their cross product is a*b=2i-5k , what is the angle between them

Answer 1

cross product two vectors - |a ̅×b ̅ |=|c ̅ |=|a ̅ ||b| sin⁡θ

coordinates of the vector с ̅={2,0,5}

magnitude of vector |c ̅ |=√(2^2+0^2+5^2 )=√29

Then, √29=3∙3 sin⁡〖θ→θ=arcsin √29/9≈0.63 rad≈36 degree〗

angle between a ̅ and b ̅ = 36 degree