SKH121 wrote:
If a ≠ 0 and b ≠ 0, and \(a^\frac{2}{3}=b^\frac{2}{3}\) then which of the following statements must be true?
Indicate all possible values.
a) \(a/b =1\)
b) \(a/b = -1\)
c) \((a/b)^2 =1\)
d) \(a= 2/3\)
e) \(a^2 = b^2\)
f) \(a^{1/2} = b^{1/2}\)
\(a^\frac{2}{3}=b^\frac{2}{3}\) =>\(\sqrt[3]{a^2}=\sqrt[3]{b^2}\).. Thus a=b or a=-b
Let us check the options
a) \(a/b =1\).....Will not be true when a=-b
b) \(a/b = -1\).....Will not be true when a=b
c) \((a/b)^2 =1\).....Will always be true for both a=b and a=-b
d) \(a= 2/3\).....Will not be true as we do not know what is a.
e) \(a^2 = b^2\).....Will always be true for both a=b and a=-b
f) \(a^{1/2} = b^{1/2}\).....Will not be true when a=-b, as for a negative term square root is undefined.