# An easy function problem.

Level pending

Suppose there exists a function such that $Q(x,y) = x\cdot Q(x,1) + y\cdot Q(1,y) + xy.$ Allow for $$i=\sqrt{-1}$$. The value of $$Q(7i,Q(5,3i))$$ can be expressed in the form $$a+bi$$; determine $$|a+b|-13$$.

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