Question

计算：[3(x+b)^2-6(x+b)^2+9(x+b)]/[3(x+b)]-(x-b)^2;

Answer 1

原式=3(x+b)³/[3(x+b)]-6(x+b)²/[3(x+b)]+9(x+b)/[3(x+b)]-(x-b)²

=x²+2bx+b²-2x-2b+3-x²+2bx-b²

=4bx-2x-2b+3