answer

x^3ⁿ+y^3ⁿ is divisible by x+y if
(a)n is an integer n>=0
(b)n ia odd positive integer
(c)n is even positive integer
(d)n is rational

6 Answers

it will be divisible by x+y if x=-y is a root of

x^3ⁿ+y^3ⁿ

so x^3ⁿ+(-x)^3ⁿ

so the bottom line is (-1)^3ⁿ = -1

that will be for n odd +ve!

hey can u explain me the last line of ur solution???
(-1)^3ⁿ=-1
how did this come??

I meant

so x^3ⁿ+(-x)^3ⁿ = 0

which is equivalent to (-1)^3ⁿ = -1

okk..thanx

i also get the same answer bt answer given is (a)

oops the answer is right

we need

3ⁿ as odd..

that will always be odd for all integers :)

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