Jump to content

Photo

$\frac{2\sqrt{\frac{x^{2}}{2}+\frac{x}{2}+1}-x}{\sqrt{x-1}-x}\geq 1$

- - - - -

  • Please log in to reply
1 reply to this topic

#1
Mr0

Mr0

    Hạ sĩ

  • Thành viên
  • 71 posts
$\frac{2\sqrt{\frac{x^{2}}{2}+\frac{x}{2}+1}-x}{\sqrt{x-1}-x}\geq 1$

#2
Giang1994

Giang1994

    C'est la vie

  • Thành viên
  • 249 posts
Điều kiện $x\geq1$
nhận xét $\sqrt{x-1}<x$
Chuyển 1 sang thì có
$\frac{\sqrt{2x^2+2x+4}-\sqrt{x-1}}{\sqrt{x-1}-x}\geq0$
tương đương
$\sqrt{2x^2+2x+4}\leq\sqrt{x-1}$ (do mẫu âm)
......

Edited by Giang1994, 15-04-2012 - 19:24.

Don't let people know what you think





1 user(s) are reading this topic

0 members, 1 guests, 0 anonymous users