Exercise 9-5 Prove valid (note that these problems are not necessarily in order of difficulty). (1) 1. (∃x)Fx ∨ (∃x)Gx

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Exercise 9-5 Prove valid (note that these problems are notnecessarily in order of difficulty).
(1) 1. (∃x)Fx ∨ (∃x)Gx p
2. (x) ∼ Fx p
/∴ (∃x)Gx
(3)1. ∼ (x)Ax p
/∴ (∃x)(Ax ⊃ Bx)
(5)1. (∃x)Fx ⊃ (x) ∼ Gx p
2. (∃x)Ex ⊃ ∼ (x) ∼ Fx p
/∴ (∃x)Ex ⊃ ∼ (∃x)Gx
(7)1.(x)[(Fx ∨ Hx) ⊃ (Gx ⋅ Ax)] p
2. ∼ (x)(Ax ⋅ Gx) p
/∴ (∃x) ∼Hx
(9)1.(x)[(Fx ∨ Gx) ⊃ Hx] p
2. (x)[(Hx ∨ Kx) ⊃ Lx] p
/∴ (x)(Fx ⊃Lx)