The constant term in the expansion of $\left(2x+1\right)\left(3x+2\right)\left(x+3\right)=0$  is

$\left(6x^2+7x+2\right)\left(x+3\right)=0$

$6x^2\left(x+3\right)+7x\left(x+3\right)+2\left(x+3\right)=0$

$6x^3+18x^2=7x^2+21x+2x+6=0$

$6x^3+25x^2+23x+6=0$

$cons\tan tterm=6$

$\left(or\right)$

$1\times 2\times 3=6$

(Product of all constants in the products)