apply Nat.add_le_of_le_sub _ blah3
case h
a b x : ℕ
⊢ (x + 1 + 1) ^ a - (x + 1) ^ a + (x + 1) ^ (a + b) ≤ (x + 1 + 1) ^ (a + b)

case h
a b x : ℕ
⊢ (x + 1) ^ a ≤ (x + 1 + 1) ^ a

case h
a b x : ℕ
⊢ (x + 1) ^ a ≤ (x + 1) ^ (a + b)
a b x : ℕ
⊢ (x + 1) ^ (a + b) ≤ (x + 1 + 1) ^ (a + b)

case h
a b x : ℕ
⊢ (x + 1) ^ a ≤ (x + 1 + 1) ^ a

case h
a b x : ℕ
⊢ (x + 1) ^ a ≤ (x + 1) ^ (a + b)