(x−1)4+(x−5)4=82⇒{(x−1)2}2+{(x−5)2}2=82⇒{(x−1)2−(x−5)2}2+2(x−1)2(x−5)2=82⇒{x2−2x+1−x2+10x−25}2+2(x2−2x+1)2(x2−10x+25)2=82⇒(8x−24)2+2(x4−10x3+25x2−2x3+20x2−50x+x2−10x+25)=82⇒64(x2−6x+9)+2(x4−12x3+46x2−60x+25)=82⇒156x2−384x+576+2x4−24x3+92x2−120x+50=82⇒2x4−24x3+248x2−504x+544=0