(2t^2−t−8)(2t^2+2t−1)
= (2t^2+−t+−8)(2t^2+2t+−1)
= (2t^2)(2t^2) + (2t^2)(2t) + (2t^2)(−1) + (−t)(2t^2) + (−t)(2t) + (−t)(−1) + (−8)(2t^2) + (−8)(2t) + (−8)(−1)
=4t^4+4t^3−2t^2−2t^3−2t^2+t−16t^2−16t+8
=4t^4+2t^3−20t^2−15t+8
Sorry if I made it too complicated
