hướng dẫn giải bài toán khó trường Lê Minh Xuân của bạn Sang

By Trang Ánh Nam -

(2+1)(22+1)(24+1)(28+1)(216+1)-232
=1.(2+1)(22+1)(24+1)(28+1)(216+1)-232
=(2-1)(2+1)(22+1)(24+1)(28+1)(216+1)-232
=(22-1)(22+1)(24+1)(28+1)(216+1)-232
=(24-1)(24+1)(28+1)(216+1)-232
=(28-1)(28+1)(216+1)-232
=(216-1)(216+1)-232
=232-1-232
=-1.

Bài này không khó mà cũng không dễ, vì số mà các bạn có thể định hướng giải bài bị ẩn đi, trong bài giải trên là số 1 mà T tô đỏ.

Một số lưu ý về kiến thức:
  • khi ta nhân với số 1 thì biểu thức không thay đổi.
  • 1=2-1
  • bài trên chỉ dùng hằng đẳng thức số 3.
Chúc các bạn hiểu bài, nếu có bài khó thì có thể comment(bình luận) phía dưới. Cám ơn đã ghé qua.

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