Question 223839
How do you solve a problem with a negative under a radical sign. For example the square root of -20. Is the answer 20i?


You are almost correct.


{{{sqrt(-20)=sqrt(20*(-1))=sqrt(4*5)sqrt(-1)=sqrt(4)sqrt(5)sqrt(-1)=i2sqrt(5)}}}


where {{{i=sqrt(-1)}}}


ANSWER:  {{{sqrt(-20)=i*2sqrt(5)}}} or {{{sqrt(-20)=2sqrt(5)*i}}}


I hope the above steps were helpful.


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Good luck in your studies!


Respectfully,
Dr J