How do you simplify #sqrt(–(–7)^2)#?

2 Answers
NJ
Apr 17, 2018

#=>7i#

Explanation:

#sqrt(-(-7)^2)#

#=sqrt(-49)#

#=sqrt((49)*(-1))#

#=sqrt(49)*sqrt(-1)#

#=sqrt(7^2)*sqrt(-1)#

#=(7)*(i)#

#=7i#

Monzur R.
Apr 17, 2018

#sqrt(-(-7)^2)=+-7i#

Explanation:

#sqrt(-(-7)^2)=sqrt(-49)=sqrt(-1)sqrt(49)=+-i7=+-7i#

Over #RR#, we would only take the positive square root of #sqrt(a^2)#, but the square root function is multi-variable over #CC#, so we take both roots.

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