What is the error in the proof? (proof in details)

100 = 100
10 (10) = (-10)(-10)
sqrt((10(10) = sqrt((-10)(-10)
10 = -10

1 Answer
Jul 24, 2018

Below

Explanation:

There is an error in the last line

In the third line
sqrt(10(10))=sqrt(-10(-10))

Remember that "negative" times " negative" = "positive"

Hence, sqrt(10(10))=sqrt(-10(-10)) becomes sqrt(10(10))=sqrt(10(10))

therefore, your fourth line should say 10=10