How do you simplify #(4+2i)(-4+2i)#?
1 Answer
Aug 9, 2016
Explanation:
Expand the brackets using, for example, the FOIL method.
#(4+2i)(-4+2i)=-16+cancel(8i)-cancel(8i)+4i^2#
#color(orange)"Reminder" color(red)(|bar(ul(color(white)(a/a)color(black)(i^2=(sqrt(-1))^2=-1)color(white)(a/a)|)))# Hence
#-16+4i^2=-20#
#rArr(4+2i)(-4+2i)=-20#
