in the second example, just by finding n2=9, we can conclude that n=3. so why did we have to find n3=27?

From the first equation, we have *n*^{2 }= 9,

since it is given that *n *is an integer, so from the above equation we get two values of *n *as +3 and -3

but it is from the second equation that is *n*^{3 }= 27, we can have the conclusion that we have to take *n* = 3. The given conditions are satisfied for *n* = 3

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