GPT :
1. $x^6 - 2x^5 + x^4 - 7x^3 +x^2 - 2x +1 =0$
2. $x^5+5x^4+3x^3-13x^2-24x-36=0$
3. $3x^5+4x^4-6x^3-7x^2+2x+2=0$
4.$x^4-11x^2+12x=0$
5. $x^4+3x-6x^2+6x+1=0$
6. $x^4+2x^2+10x+4=5x^3$
7. $15x^4+11x^3-78x^2-71x-9$
8. $6(x+1)^4=17x^3+52x^2+37x+30=0$