<prompt> Kama fx x4 x2 5x, kutathmini f5 - f-5.  <response>: Tunaweza kwanza kugawanya kazi katika sehemu mbili: fx x4 x2 5x gx hx, ambapo gx x4 x2 na hx 5x Tunaweza kisha kutumia ukweli kwamba gx ni kazi hata, na hx ni kazi odd. Hii ina maana kwamba: gx g-x kwa wote halisi x hx -h-x kwa wote halisi x Kutumia mali hizi, tunaweza kurahisisha usemi: f5 - f-5 g5 5 - g-5 h-5 g5 - g-5 h5 - --5 g5 - f h h h h h h h h h h h h 2 h h h h 0 h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h h 