x^4+x^3+2x+x+1
=(x^4+x^3+x^2)+(x^2+x+1)
=x^2(x^2+x+1)+(x^2+x+1)
=(x^2+1)(x^2+x+1)
x^4+x^3+2x+x+1
=(x^4+2x^2+1)+(x^3+x)
=(x^2+1)^2+x(x^2+1)
=(x^2+1)(x^2+x+1)
x^4+x^3+2x+x+1
=(x^4+x^3+x^2)+(x^2+x+1)
=x^2(x^2+x+1)+(x^2+x+1)
=(x^2+1)(x^2+x+1)
x^4+x^3+2x+x+1
=(x^4+2x^2+1)+(x^3+x)
=(x^2+1)^2+x(x^2+1)
=(x^2+1)(x^2+x+1)