How do you simplify #(-1-5i)(-1+5i)#?

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Answer 1 · 2018-08-10T17:59:18

#26#

#(-1-5i)(-1+5i)#

Use FOIL to distribute:
#-1 * -1 = 1#

#-1 * 5i = -5i#

#-5i * -1 = 5i#

#-5i * 5i =-25i^2#

Combine them together:
#1 - 5i + 5i - 25i^2#

Simplify:
#1 - 25i^2#

We know that #i^2 = -1#, so:
#1 - 25(-1)#

#=1 + 25#

#=26#

Hope this helps!