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The Function F(X) = X9 + 3x7 + 64 is Increasing on

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Question

The function f(x) = x9 + 3x7 + 64 is increasing on

Options

  • R

  • (−∞, 0)

  • (0, ∞)

  •  R0

MCQ
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Solution

 R

\[f\left( x \right) = x^9 + 3 x^7 + 64\]

\[f'\left( x \right) = 9 x^8 + 21 x^6 > 0, \forall x \in R\]

\[\text { So, f(x) is increasing on R } .\]

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Chapter 16: Increasing and Decreasing Functions - Exercise 17.4 [Page 42]

APPEARS IN

R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 16 Increasing and Decreasing Functions
Exercise 17.4 | Q 30 | Page 42

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