Answer:
7[tex]x^{3}[/tex] -3
Step-by-step explanation:
You want to simplify: (3x³+2-x³) - (-5x³+2²+1)
(3x³+2-x³) - (-5x³+2²+1) = 3x³ + 5x³ +2 -x³ - 2²-1
=7x^3 - 3