case h
x✝ : ℝ
⊢ toReal ↑x✝ ≤ π
θ : Angle
⊢ toReal θ ≤ π
induction θ using Real.Angle.induction_on
case h.e'_4
x✝ : ℝ
⊢ π = -π + 2 * π
case h
x✝ : ℝ
⊢ toReal ↑x✝ ≤ π
convert toIocMod_le_right two_pi_pos _ _
no goals
case h.e'_4
x✝ : ℝ
⊢ π = -π + 2 * π
ring