Điền 1 từ thích hợp vào ô trống
Throughout (0) _________ 1990s I worked (1) ______ an accountant in a large furniture factory in London. I had a responsible job and was earning (2) ________ good living. Unfortunately, the company wasn't doing so well, and in 1999 I was (3) _______ redundant. My husband and I (4) _____ always wanted to run (5) _____ own business, and we both felt that now was a good time to (6) ______ a risk and do somthing different. Johnathan, my husband, gave (7) ______ his well-paid but stressful job in the City and we bought a pub in a village near York. It took (8) _____ both quite a long time to (9) ____ used to living in the countryside. Everything happens (10) ____ much slower pace here, but the people are friendlier than in London and we coudn't imagine going back (11) ____ to live. We still work as hard (12) ____ we did before, but it's so much more satisfying working for yourself
@Nguyễn Nhật Minh
@Cuồng Khải Nguyên
@Aki Tsuki
@Yukru
Help me, plz!!!
Bài 1:
a) Cho a, b, c, d , là các số nguyên thỏa mãn a - b = c + d. Chứng minh rằng a2 + b2 + c2 + d2 luôn là tổng của ba số chính phương
b) Cho a, b, c, d là các số nguyên thỏa mãn a + b + c + d = 0. Chứng minh rằng ( ab - cd )( bc - da )( ca - db ) là số chính phương