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The function f(x) = x3 + 3x is increasing in interval ______. - Mathematics

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प्रश्न

The function f(x) = x3 + 3x is increasing in interval ______.

विकल्प

  • (– ∞, 0)

  • (0, ∞)

  • R

  • (0, 1)

MCQ
रिक्त स्थान भरें

उत्तर

The function f(x) = x3 + 3x is increasing in interval R.

Explanation:

f(x) = x3 + 3x

`\implies` f'(x) = 3x2 + 3

= 3(x2 + 1) > 0

So function increases for all real values of x ∈ R.

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2022-2023 (March) Delhi Set 3

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