Question

Find the product and write the answer in standard form.
$(2-4i)(3+7i)$

• A. $34+2i$
• B. $-5-3i$
• C. $5+3i$
• D. $5-3i$

Answer 1

The correct option is A $34+2i$

Given $z=(2-4i)(3+7i)$

$z=\left[2\right(3+7i)-4i(3+7i\left)\right]$

$=[6+14i-12i-28i^2]$

$=[34+2i]$............[since, $i^2=-1$]