Math

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Across
  1. 3. No!
  2. 4. Infinity when it stands up.
  3. 6. X
  4. 7. You can't divide by him
  5. 8. Number of Hiragana vowels
Down
  1. 1. Sounds like something naughty
  2. 2. I write it with a line, you write it without
  3. 5. twice is ___ times
  4. 6. x^3-3x^2+3x-1 = (x-1)^(_)