Hi everyone. Sorry, it’s my first time using this and I don’t know if this has been asked before.
Basically, on the second day of week 1 when exponent rules were being discussed, Greg pointed out that -5^2 is a negative number and it would only be positive if it was -(5)^2.
But, on day 3 he says that if x^4= 625 then the answer would be 5 or -5. My assumption is that you consider both the negative and positive option when the base is unknown, but when the base is known (and if it is negative) then you know for sure that it is negative.
I am very confused on this matter. Further explanation on this or any links to specific guides discussing this particular topic would be extremely appreciated. Thank you in advance!
Both are negative actually. Only (-5)^2 is positive - the subtle difference is very important.
Yes, you’re right. Thank you! It was a mistake on my end.
But that still begs the question of how come -5^2 = -25 but the answer to x^4=625 is -/+5
Same thing actually. Notice that (-5)^4 = 625 but -5^4 = -625.