PNG  IHDRS9}0PLTE@@@ftRNSS pHYsetEXtTitleInftyEditor MathImageytEXtAuthorAdministrator*tEXtDescription $ f(x, y) $ItEXtCopyrightInftyProject@$tEXtCreation Time r'rr'rr IDATx͓ )e-Pe g*`y?#O]]q2Ԩ4Goc/+t :9U KtBW6%uV9\v#S4!_g B7IIIENDB`