In the Text,we Showed That the Multiproduct Cost Function $C \left( Q _ { 1 } , Q _ { 2 } \right) = f + a Q _ { 1 } Q _ { 2 } + \left( Q _ { 1 } \right) ^ { 2 } + \left( Q _ { 2 } \right) ^ { 2 }$

Essay

In the text,we showed that the multiproduct cost function $C \left( Q _ { 1 } , Q _ { 2 } \right) = f + a Q _ { 1 } Q _ { 2 } + \left( Q _ { 1 } \right) ^ { 2 } + \left( Q _ { 2 } \right) ^ { 2 }$ exhibits cost complementarity whenever $a < 0$ and economies of scope whenever $f - a Q _ { 1 } Q _ { 2 } > 0$ .
a.Can cost complementarity exist without economies of scope?
b.Can there be economies of scope when cost complementarities exist?