Q3 of 30 Page 2

Question-3 Show that x + a is a factor of xn +an for any odd +ve integer n.

Let f(x) = xn + an
x + a will be the factor of xn +an if f(-a) = 0 
Now f(- a) = (- a)n+ an =  0    (since n is a odd +ve integer)
Thus (x + a) is a factor of xn + an.

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