a)\(A\left(x\right)=6x^4+6x^3-5x-17\)
\(B\left(x\right)=6x^4+6x^3-2x^2-5x-15\)
b)\(A\left(x\right)+B\left(x\right)=6x^4+6x^3-5x-17+6x^4+6x^3-2x^2-5x-15\)
\(A\left(x\right)+B\left(x\right)=12x^4+12x^3-2x^2-10x-32\)
\(A\left(x\right)-B\left(x\right)=6x^4+6x^3-5x-17-6x^4-6x^3+2x^2+5x+15\)
\(A\left(x\right)-B\left(x\right)=2x^2-2\)