Answer
$G'(q)=-2q^{-2}-2q^{-3}$
Work Step by Step
Make an «u» substitution in order to apply the chain rule and make it easier
$G(u)=u^2$
$u=1+q^{-1}$
$u'=-q^{-2}$
Derivate
$G'(u)=2u*u'$
Undo the substitution
$G'(q)=2(1+q^{-1})(-q^{-2})$
$G'(q)=-2q^{-2}-q^{-3}$