Asked by Robbie
Question is Simplify 625^3/4. answer is 125.
What isn't the answer +/-125?
What isn't the answer +/-125?
Answers
Damon
well, I suppose I would check
-125^4/3
-125^1/3 = -5
then(-5)^4 = 625
so it looks like you are right to me
-125^4/3
-125^1/3 = -5
then(-5)^4 = 625
so it looks like you are right to me
Reiny
625^3/4
= (√ (√625) )^3
= (√25)^3
= 5^3
= 125
by definition of the square root operation:
return the positive square root of the number
e.g. √4 = 2 , even your calculator is programmed that way
as opposed to
x^ = 4
We usually write as our next step
x = ± 2
skipping the all important steps between:
x^2 = 4
±x = √4
±x = 2 ----> x = 2 OR -x = 2, which is
x = ± 2
This is critical in statements such as
x^2 > 4
It would be incorrect to say x > ± 2
instead we have to say:
x^2 > 4
±x > 2
thus x > 2 OR -x > 2
giving us the correct solution :
x > 2 OR x < -2
= (√ (√625) )^3
= (√25)^3
= 5^3
= 125
by definition of the square root operation:
return the positive square root of the number
e.g. √4 = 2 , even your calculator is programmed that way
as opposed to
x^ = 4
We usually write as our next step
x = ± 2
skipping the all important steps between:
x^2 = 4
±x = √4
±x = 2 ----> x = 2 OR -x = 2, which is
x = ± 2
This is critical in statements such as
x^2 > 4
It would be incorrect to say x > ± 2
instead we have to say:
x^2 > 4
±x > 2
thus x > 2 OR -x > 2
giving us the correct solution :
x > 2 OR x < -2