rw [b_eq_kpOne]
φ : ℝ → ℂ
a b : ℝ
k : ℤ
b_eq_kpOne : b = ↑k + 1
φDiff : ∀ x ∈ [[a, b]], HasDerivAt φ (deriv φ x) x
derivφCont : ContinuousOn (deriv φ) [[a, b]]
⊢ b < ↑(k + 1) + 1
φ : ℝ → ℂ
a b : ℝ
k : ℤ
b_eq_kpOne : b = ↑k + 1
φDiff : ∀ x ∈ [[a, b]], HasDerivAt φ (deriv φ x) x
derivφCont : ContinuousOn (deriv φ) [[a, b]]
⊢ ↑k + 1 < ↑(k + 1) + 1