f{xy), x = X(s, t), y = Y(s, t), then u is a function of s, t, call it (a) Write ᎧF /Ꭷs and ᎧF /ot in terms of of / oa, ò f / òy, ᏭX / os, OX / Ꭷt, ᎧY / Os, and _ᎧY ] ᎾᎿ (b) Suppose that ƒ/(əxəy) = 0²ƒ/(Əyər), show that 7. (1pt) Let u u = F ( 85 k ) . ᎧᎵ - fᎧ · ( = . Ꮎx ds2 4 ( Ꭹ ) . Os ᎧX Ꭷ Ꭷ f of Ꮽ-Y 0s Ꮽs oroy " òy ( ) * + - f ( ᎧY 0s , dy? მა +2-

Fig: 1