P y E Servicios Integrales 659 likes 1 talking about this Local ServiceR ules on let t ing t his pr oper t y P ropert i es c an be rent ed i f t hey hav e an energy rat i ng f rom A t o E I f t he propert y i s rat ed F or G, i t c annot be l et , unl es s an ex em pt i on has been regi s t ered You c an read gui danc e f or l andl ords on t he regul at i ons and ex em pt i ons ( h tps /w gov uk ida nc em r y e ffi c i e n c y s ta n d a r d l a n d lY = ex p ( ex)2 4 1 ( ex) 2 1 y = ex p e2x 4ex 2 Our original equation is valid only for y > 0, and p e2x 4ex > p e2x = ex, so our nal answer is y = ex p e2x 4ex 2 2 The best way to check our work here might be to choose some simple values for x and evaluate both sides of the original equation using a calculator 4 ex e x ex e x = y We start by applying the hint, letting u = ex Pecharic Et Le Py La Societe D Etudes Scientifiques De L Aude P a y e e words