$x+21 / 2(2x+3)(3x-2)$
The 2 in the denominator represents a problem for me:
$x+21 / 2(2x+3)(3x-2) = A / 2(2x+3) * B / 2(3x-2)$ $x+21 = A(2)(3x-2) + B(2x+3)$
$x+21 / 2(2x+3)(3x-2)$
The 2 in the denominator represents a problem for me:
$x+21 / 2(2x+3)(3x-2) = A / 2(2x+3) * B / 2(3x-2)$ $x+21 = A(2)(3x-2) + B(2x+3)$
Do it this way:
$$\frac{1}{2}\cdot \frac{x+21}{(2x+3)(3x-2)}=\frac{1}{2}\cdot (\frac{A}{2x+3}+\frac{B}{3x-2})$$ Then continue.