The equilibrium constant expression for KSP of Sr3(PO4)2 is
KSP={(Sr^2+)^3 (PO4^3-)^2/ Sr3(PO4)2}
Explanation
write the ionic equation for Sr3(PO4)2
Sr3(PO4)2 → 3Sr^2+ + 2 PO4^3-
KSP is given by (concentration of the products raised to their coefficient /concentration of reactants raised to their coefficient)