हिंदी

If f(x) = 2x and g(x) = x22+1, then which of the following can be a discontinuous function ______.

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प्रश्न

If f(x) = 2x and g(x) = `x^2/2 + 1`, then which of the following can be a discontinuous function ______.

विकल्प

  • f(x) + g(x)

  • f(x) – g(x)

  • f(x) . g(x)

  • `("g"(x))/("f"(x))`

MCQ
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उत्तर

If f(x) = 2x and g(x) = `x^2/2 + 1`, then which of the following can be a discontinuous function `("g"(x))/("f"(x))`.

Explanation:

We know that the algebraic polynomials are continuous functions everywhere.

∴ f(x) + g(x) is continuous   .....`[(∵ "Sum, difference and product"),("of two continuous functions is"),("also continuous")]`

f(x) – g(x) is continuous

f(x) . g(x) is continuous

`("g"(x))/("f"(x))` is only continuous if g(x) ≠ 0

∴ `("f"(x))/("g"(x)) = (2x)/(x^2/2 + 1) = (4x)/(x^2 + 2)`

Here, `("g"(x))/("f"(x)) = (x^2/2 + 1)/(2x) = (x^2 + 2)/(4x)`

Which is discontinuous at x = 0.

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अध्याय 5: Continuity And Differentiability - Exercise [पृष्ठ ११३]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 12
अध्याय 5 Continuity And Differentiability
Exercise | Q 83 | पृष्ठ ११३

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