`BookProof.ChapterE.exp_J` (t : ℝ) : NormedSpace.exp (t • J) = !![Real.cos t, -Real.sin t; Real.sin t, Real.cos t]

Initializing...

`BookProof.ChapterE.exp_J` (t : ℝ) : NormedSpace.exp (t • J) = !![Real.cos t, -Real.sin t; Real.sin t, Real.cos t] · Prove2Me