Question

When $a=3$, $b=0$, and $c=-2$ , find the value of :

$ab+2bc+3ca+4abc$

Answer 1

Compute the required value:

$ab+2bc+3ca+4abc$

substituting $a=3$, $b=0$, and $c=-2$ in given expression we get

$$\begin{gathered} ab+2bc+3ca+4abc=3\times 0+2\times 0\times \left(-2\right)+3\times \left(-2\right)\times 3+4\times 3\times 0\times \left(-2\right) \\ =0+0-18+0 \\ =-18 \end{gathered}$$

Hence , the value of $ab+2bc+3ca+4abc$ is $-18$