● ○ ■ ◆ ▸ ☐☑ ✔

μ ρ
x̄
σ
p̂
Δ
λ
√
×
≠ ≥ ≤
≈
±
←
⇠
↑
→
↓
⇜
⇝
↔
∝
Δ
From here:
√ — alt-8730
∛ — alt-8731
² — alt-0178
³ — alt-0179
° — alt-0176
· — alt-0183
× — alt-0215
÷ — alt-0247
± — alt-0177
∫ — alt-8747
∬ — alt-8748
∭ — alt-8749
∑ — alt-8721
∏ — alt-8719
→ — alt-8594
∞ — alt-8734
≈ — alt-8776
≠ — alt-8800
≡ — alt-8801
π — alt-0960
θ — alt-0952
φ — alt-0966
δ — alt-0948
ε — alt-0949
∈ — alt-8712
∀ — alt-8704
∃ — alt-8707
∠ — alt-8736
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Not for math:

☃☄⌘☠๛ ★☆☁☯♛∴⌬⌨❣甴曱⊞҉ஐ… ⋱ ⋯ ⋰ ⋮♉⁂