dse 2006 51 doubt

[leon]

please help with 51st one

[Sris]

LOOK...
at d world price p^*(before the tariff)
dd wud be  p^*=a -qd that implies qd=a-p^*
ss wud be p^*=bqs that implies qs=p^*/b

now after the tariff domestic price rises to p^*+t
dd wud be qd=a-p^* -t(put p^*+t in d dd function)
ss wud be qs= p^*+t/b(put p^*+t in d ss function)
 
now iif u cud recall the tariff diagram u wud know deadweight loss = sum of two triangles)

=1/2((p^*+t/b) -p^*/b)t +1/2( a-p^*-(a -p^*-t))t
=t^2(1+b)/2b

[leon]

Thanks