MATH CROSS -WORD PUZZLE

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Across
  1. 2. defined only for positive reals
  2. 3. method of proving math statements
  3. 8. plane to represent complex number
  4. 10. measure
  5. 14. steepness
  6. 15. z-coordinate
  7. 16. length of a line segment used in conics
  8. 17. mutually exclusive
  9. 18. difference of extreme values
Down
  1. 1. arrangement
  2. 4. rate of change
  3. 5. eight sections
  4. 6. reflector
  5. 7. specific ellipse
  6. 9. variation
  7. 11. pictorial representation
  8. 12. branch of Maths
  9. 13. solution of inequalities
  10. 14. well-defined group