Reiknireglur – Æfing 1.1 – Lausnir

  1. 7 – 32 = 7 – 9 = -2
  2. 42 – 22 = 16 – 8 = 8
  3. (6 – 2)2 = 42 = 16
  4. 62 + 52 = 36 +25 = 61
  5. (6 + 5)2 = 112 = 121
  6. 92 – 42 = 81 – 16 = 65
  7. (9 – 4 )2 = 52 = 25
  8. 2·4 + 325 = 8 + 9·5 = 8 +45 = 53
  9. 2(4 + 32)·5 = 10(4+9) = 10·13 = 130