Question

(8x^3+5x^2-12x+10)%(x^2-3)

Answer 1

If the % sign is a division symbol, then the answer is
8x + 5 + remainder of (12x+25)/(x^2 -3)

If it a multiplication sign, then the answer is
64x^4 + 45x^3 - 71x^2 + 20x + 50