Hello i don't know how to do this problem ... plesae help me out ... thanks

determine the smallest positive integers, n , which satisfies the equation

n3 + 2n2 = b

where b is the square of an odd integer

i thoguht about replacing b by x2 , and move the x2 to the left side, then i'm kinda stuck ... please show me ...

thank you very much !


Hi David,

If you replace b by x2 then you can write the equation as

n2(n + 2) = x2

From this equation you can see that n + 2 is a square and hence n must be 2 less than a square.

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