Question Number 139932 by Ar Brandon last updated on 02/May/21
$$\mathrm{F}\left(\mathrm{x}\right)=\frac{\mathrm{1}}{\mathrm{h}^{\mathrm{2}} }\int_{\mathrm{0}} ^{\mathrm{h}} \mathrm{d}\xi\int_{\mathrm{0}} ^{\mathrm{h}} \mathrm{f}\left(\mathrm{x}+\xi+\eta\right)\mathrm{d}\eta \\ $$$$\mathrm{Calculate}\:\mathrm{F}''\left(\mathrm{x}\right) \\ $$