51. a two-dimensional lattice has the basis vectors 2i and i +2. the basis vectors of the reciprocal lattice are (a) iiand = (b) mi-i and - c)- i-5iand - (d) ti

51. A two-dimensional lattice has the basis vectors 2i and i +2. The basis vectors of the reciprocal lattice are (A) iiand = (B) mi-i and - C)- i-5iand - (D) Ti-iand mi