no goals
k : Type u₁
G : Type u₂
R : Type ?u.365398
inst✝¹ : Semiring k
inst✝ : Mul G
a₁ a₂ : G
b₁ b₂ : k
⊢ (sum (single a₂ b₂) fun a₂ b₂ => single (a₁ * a₂) (0 * b₂)) = 0
simp only [zero_mul, single_zero, sum_zero]
no goals
k : Type u₁
G : Type u₂
R : Type ?u.365398
inst✝¹ : Semiring k
inst✝ : Mul G
a₁ a₂ : G
b₁ b₂ : k
⊢ single (a₁ * a₂) (b₁ * 0) = 0
rw [mul_zero, single_zero]