मराठी

Let f(x) be a polynomial function of degree 6 such that ddx(f(x)) = (x – 1)3 (x – 3)2, then Assertion (A): f(x) has a minimum at x = 1.

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प्रश्न

Let f(x) be a polynomial function of degree 6 such that `d/dx (f(x))` = (x – 1)3 (x – 3)2, then

Assertion (A): f(x) has a minimum at x = 1.

Reason (R): When `d/dx (f(x)) < 0, ∀  x ∈ (a - h, a)` and `d/dx (f(x)) > 0, ∀  x ∈ (a, a + h)`; where 'h' is an infinitesimally small positive quantity, then f(x) has a minimum at x = a, provided f(x) is continuous at x = a.

पर्याय

  • Both (A) and (R) are true and (R) is the correct explanation of (A).

  • Both (A) and (R) are true but (R) is not the correct explanation of (A).

  • (A) is true but (R) is false.

  • (A) is false but (R) is true.

MCQ
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उत्तर

Both (A) and (R) are true and (R) is the correct explanation of (A).

Explanation:

`d/dx (f(x))` = (x – 1)3 (x – 3)2

Assertion : f(x) has a minimum at x = 1 is true as

`d/dx (f(x)) < 0, ∀  x ∈ (1 - h, 1)` and `d/dx (f(x)) > 0, ∀  x ∈ (1, 1 + h)`; where 'h' is an infinitesimally small positive quantity, which is in accordance with the Reason statement.

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