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If agtbgt1 then a^(n)-b^(n)gtn(a-b) for ...

If `agtbgt1` then `a^(n)-b^(n)gtn(a-b)` for every +ive integer `n ge2`.True or False.

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To determine whether the statement "If \( a > b > 1 \) then \( a^n - b^n > n(a - b) \) for every positive integer \( n \geq 2 \)" is true or false, we will analyze the inequality step by step. ### Step-by-Step Solution: 1. **Understanding the Given Condition**: We are given that \( a > b > 1 \). This means both \( a \) and \( b \) are positive numbers greater than 1. 2. **Consider the Expression**: We need to analyze the expression \( a^n - b^n \) and compare it to \( n(a - b) \). 3. **Using the Binomial Theorem**: The expression \( a^n - b^n \) can be factored using the difference of powers: \[ a^n - b^n = (a - b)(a^{n-1} + a^{n-2}b + a^{n-3}b^2 + \ldots + b^{n-1}) \] Here, \( a^{n-1} + a^{n-2}b + \ldots + b^{n-1} \) is a sum of \( n \) terms. 4. **Analyzing the Sum**: Since \( a > b > 1 \), each term in the sum \( a^{n-1}, a^{n-2}b, \ldots, b^{n-1} \) is positive. Therefore, the entire sum \( a^{n-1} + a^{n-2}b + \ldots + b^{n-1} \) is greater than \( n \cdot b^{n-1} \) (since \( b^{n-1} \) is the smallest term in the sum). 5. **Inequality Formation**: Thus, we can write: \[ a^n - b^n = (a - b)(a^{n-1} + a^{n-2}b + \ldots + b^{n-1}) > (a - b)(n \cdot b^{n-1}) \] 6. **Comparing with \( n(a - b) \)**: We need to show that: \[ (a - b)(n \cdot b^{n-1}) > n(a - b) \] Dividing both sides by \( a - b \) (which is positive since \( a > b \)): \[ n \cdot b^{n-1} > n \] This simplifies to: \[ b^{n-1} > 1 \] Since \( b > 1 \), raising \( b \) to any positive power \( n-1 \) (where \( n \geq 2 \)) will indeed yield a result greater than 1. 7. **Conclusion**: Therefore, we conclude that: \[ a^n - b^n > n(a - b) \] is true for every positive integer \( n \geq 2 \). ### Final Answer: The statement is **True**.
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ML KHANNA-INEQUALITIES-PROBLEM SET (1)(TRUE AND FALSE)
  1. If a,b,c are in HP, then prove that (a+b)/(2a-b)+(c+b)/(2c-b)gt4.

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  2. If a > ba n dn is a positive integer, then prove that a^n-b^n > n(a b)...

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  3. If agtbgt1 then a^(n)-b^(n)gtn(a-b) for every +ive integer n ge2.True ...

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  4. 2/(b+c)+2/(c+a)+2/(a+b)gt9/(a+b+c)

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  5. If S=a+b+c then prove that (S)/(S-a)+(S)/(S-b)+(S)/(S-c) gt (9)/(2) wh...

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  6. 3/(b+c+d)+3/(c+d+a)+3/(d+a+b)+3/(a+b+c)gt16/(a+b+c+d)

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  7. n(n+1)^(3)lt8(1^(3)+2^(3)+3^(3)+………+n^(3))

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  8. If a, b, c are in H.P. and they are distinct and positive then prove t...

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  9. Sum of the nth powers of the m^(th) power of n even numbers is gtn(n+1...

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  10. If a,b,c are real numbers such that a^(2)+b^(2)+c^(2)=1 then ab+bc+cag...

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  11. In any triangle the semi perimeter is greater than each of its sides.

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  12. The sum of the cubes of the legs of a right angled triangle is less th...

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  13. Thesum of the hypotenuse and the altitude of a right angled triangle d...

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  14. The area of an arbitrary triangle is less than one fourth the square o...

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  15. If x,y,z are all positive and x lt y lt z, then (x^(2))/zlt(x^(2)+y^(2...

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  16. If 0ltalpha(1)ltalpha(2)lt……….ltalpha(n)lt(pi)/2 then tan alpha(1)lt...

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  17. If A+B+C=pithen "tan"^(2)A/2+"tan"^(2)B/2+"tan"^(2)C/2ge1.

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  18. Prove that 2sinx + tanx ge3x, for all x in [0, pi/2].

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  19. (a(1)^(2)+a(2)^(2)+….a(n)^(2)) (b(1)^(2)+b(2)^(2)+…..+b(n)^(2))ge(a(1...

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  20. A.M. of the square root of products taken two together on n+ve quantit...

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