17-4 0 ④ Deriving the IS curve Y=C+I+G =Co+b(Y-To-tY)+Io-er+G =(Co-bTo+To+G)+b(1-t)Y-er 1 Y-1(1(Co-bTo+G+Io-er) Y=a(A-er) AY r= e ea Economics ECONOMICS MANAGEMENT SCHOOL,TONGJI UNIVERSITYEconomics ECONOMICS & MANAGEMENT SCHOOL, TONGJI UNIVERSITY 17-4 Deriving the IS curve (C bT I G) b(1 t )Y er C b(Y T tY) I er G Y C I G 0 0 0 0 0 0 - - - - - - = + + + = + + + = + + ea Y e A r Y a(A er) (C bT G I er) 1 b(1 t ) 1 Y 0 0 0 - - - - - - = = = + +