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Prove the statement by the Principle of Mathematical Induction :For any natural number n, xn – yn is divisible by x – y, where x integers with x ≠ y. |
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Answer» According to the question, P(n) = xn – yn is divisible by x – y, x integers with x ≠ y. So, substituting different values for n, we get, P(0) = x0 – y0 = 0 Which is divisible by x − y. P(1) = x − y Which is divisible by x − y. P(2) = x2 – y2 = (x +y)(x−y) Which is divisible by x−y. P(3) = x3 – y3 = (x−y)(x2+xy+y2) Which is divisible by x−y. Let P(k) = xk – yk be divisible by x – y; So, we get, ⇒ xk – yk = a(x−y). Now, we also get that, ⇒ P(k+1) = xk+1 – yk+1 = xk(x−y) + y(xk−yk) = xk(x−y) +y a(x−y) Which is divisible by x − y. ⇒ P(k+1) is true when P(k) is true. Therefore, by Mathematical Induction, P(n) xn – yn is divisible by x – y, where x integers with x ≠ y which is true for any natural number n. |
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