Is (x^3)/y = x + x/y?
a) y=8
b) y = (x^2) - 1
Can anyone explain this DS problem?
DS problem in stat2
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Let simplify (x^3)/y = x + x/yvishalwin wrote:Is (x^3)/y = x + x/y?
a) y=8
b) y = (x^2) - 1
Can anyone explain this DS problem?
(x^3)/y = x + x/y
(x^3)/y - (x/y) = x
x/y * (x^2 - 1) = x
1/y * (x^2 - 1) = 1
(x^2 - 1) = y
Rephrased question: is (x^2 - 1) = y
a)y = 8
(x^2 - 1) = 8
We don't know what x is, so we cant answer this part
not sufficient
b)y = (x^2) - 1
this is equal to the rephrased question
sufficent
ans = b