Question

2b²-bb³+1 - b-1b²-b+1

Answer 1

$frac{2b^{2}-b} {b^{3}+1}- frac{b-1}{b^{2}-b+1}= frac{2b^{2}-b} {(b+1)(b^{2}-b+1)}- frac{b-1}{b^{2}-b+1}= frac{2b^{2}-b-b^{2}+1}{(b+1)(b^{2}-b+1)}= frac{b^{2}-b+1} {(b+1)(b^{2}-b+1)}= frac{1}{b+1}$