no goals
n : Int
d a : Nat
a0 : a ≠ 0
⊢ mkRat (↑a * n) (a * d) = mkRat n d
if d0 : d = 0 then simp [d0] else
rw [← normalize_eq_mkRat d0, ← normalize_mul_left d0 a0, normalize_eq_mkRat]
no goals
n : Int
d a : Nat
a0 : a ≠ 0
d0 : d = 0
⊢ mkRat (↑a * n) (a * d) = mkRat n d
simp [d0]
no goals
n : Int
d a : Nat
a0 : a ≠ 0
d0 : ¬d = 0
⊢ mkRat (↑a * n) (a * d) = mkRat n d
rw [← normalize_eq_mkRat d0, ← normalize_mul_left d0 a0, normalize_eq_mkRat]