\(x^8 + 98x^4 + 1\)
\(= (x^8 + 2x^4 + 1 ) + 96x^4\)
\(= (x^4 + 1)^2 + 16x^2(x^4 + 1) + 64x^4 - 16x^2(x^4 + 1) + 32x^4\)
\(= (x^4 + 1 + 8x^2)^2 – 16x^2(x^4 + 1 – 2x^2)\)
\( = (x^4 + 8x^2 + 1)^2 - 16x^2(x^2 – 1)^2\)
\(=(x^4+8x^2+1) 2- (4x^3 -4x).2\)
\(= (x^4 + 4x^3 + 8x^2 – 4x + 1)(x^4 - 4x^3 + 8x^2 + 4x + 1)\)