Problem 1.	Premise 1 (Iab&Iba)&Ibc 1 &E 2 Iab&Iba 2 &E 3 Iab 1 &E 4 Ibc 3,4 I3 5 Iac
Problem 2.	Premise 1 (^x)(Gcd>Txd) Premise 2 Ikc&Gkd 2 &E 3 Ikc 2 &E 4 Gkd 3,4 I4 5 Gcd 1 ^E 6 Gcd>Tad 5,6 >E 7 Tad
Problem 3.	I1 1 Iaa 1 ^I 2 (^x)Ixx
Problem 4.	Premise 1 Iba 1 I2 2 Iab ~~~~ 3 ~ part II ~ Premise 4 Iab 6 I2 5 Iba

9.2ex I

Problem 1.	Premise 1 Iab&Sbc Premise 2 (^x)(Sac>Z) 1 &E 3 Iab 1 &E 4 Sbc 3 I2 5 Iba 4,5 I4 6 Sac 2 ^E 7 Sac>Z 6,7 >E 8 Z
Problem 2.	Assumption 1 ....what if Iab 1 I2 2 ....then... Iba 1-2 >I 3 Iab>Iba   Assumption 4 ....what if Iba 4 I2 5 ....then... Iab 4-5 >I 6 Iba>Iab   3,6 =I 7 Iab=Iba   7 ^I 8 (^y)(Iay=Iya)
Problem 4.	Premise 1 Iab&Iba 1 &E 2 Iab   3     4     5     6   ~~~~ 7 ~ part II ~ Premise 8 Iab 8 I2 9 Iba   10     11   8,9 &I 12 Iab&Iba