Có bao nhiêu cặp số tự nhiên (x,y) thỏa mãn đẳng thức $x^{4}$ +1=$9^{y}$
Ex5:
1 , unless i have time, i won't help you.
2 , if he studiess carefully he won't get bad marks.
3 , if dick drives carefully he won't cause accidents.
4 , if i know English, i can apply for tthe job.
Ex 6:
1, if I have lunch i won't feel hungry now.
2, unless they invite me i will come.
3, if he revise all his lessons he won't fail the exam.
4, if you walk you will see the park over there.
5, unless you don't leave me alone i ưill call the police.
6, should you arrive at the office earlier than i do, please turn on the conditioner.
7, if it isn't snow the children will go to school.
8, had he not died so young he would have been a famous a musican now.
9, unless you tell the truth i won't help you.
10, were i to take good care of the car, it wouldn't have been broken down .
