how to determine hybridisation in coordination compound having both strong and weak field ligands

dear neha 

you can take the following point into consideration 
1- the central atom make avaliable a number of empty s,p and d orbitals equal to its C.N these vacant orbital hybridise together to form hybrid orbitals . 
which are same in number as the atomic orbital hybridising together , these hybrid orbitals are vacant , equivalent in energy and have a definite geometry 
2- the non bonding metal electrons occupies the inner orbitals and they donot take part in the hybridisation, the d-orbital involved in the hybridisation may be either inner (n-1)d or outer nd orbitals 
3- vacant hybrid orbitals of the metal atom or central ion overlap with filled d orbitals of the ligand to form a covalent d bond . 
HOPE U CAN NOW ABLE TO FIND IT OUT 
REGARDS