Talvez um bagacito antes digo eu...

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T- TR= tY+T-TR

S= Yd -C= Yd -(C+cYd)=(1-c)Yd-C=(1-c)(Y-T+TR)=(1-c)(Y-T-tY+TR)-C
=(1-c)(1-t)Y+(1-c)(TR-T)-C

IM =IM- a2R+mY


Então S+(T-TR) +IM 0|1-c(1-t)+m|Y+Im+c(T-TR)-a2R


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