1) If x>0, then 1,8^x will always be greater than 1,82) If x<0, then 1,8^x will always be less than 1,83) If x<1, then 1,8^x will be less than 1,84) If x>1, then 1,8^x will be greater than 1,8.
Therefore, the answer is (3) x<1.
1) If x>0, then 1,8^x will always be greater than 1,8
2) If x<0, then 1,8^x will always be less than 1,8
3) If x<1, then 1,8^x will be less than 1,8
4) If x>1, then 1,8^x will be greater than 1,8.
Therefore, the answer is (3) x<1.