# trigonometric inequation

• Apr 13th 2013, 10:15 AM
orir
trigonometric inequation
i need to prove that for every $y\geq x\geq\frac{3}{\pi}$ : $y^{2}cos\frac{1}{y}-x^{2}cos\frac{1}{x}\geq(y^{2}-x^{2})cos\frac{1}{x}\geq\frac{(y^{2}-x^{2})}{2}$
• Apr 13th 2013, 06:17 PM
topsquark
Re: trigonometric inequation
Quote:

Originally Posted by orir
i need to prove that for every $y\geq x\geq\frac{3}{\pi}$ : $y^{2}cos\frac{1}{y}-x^{2}cos\frac{1}{x}\geq(y^{2}-x^{2})cos\frac{1}{x}\geq\frac{(y^{2}-x^{2})}{2}$

What have you been able to do so far?

-Dan
• Apr 16th 2013, 12:29 AM