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Show that the function defined by f (x) = cos (x2) is a continuous function. - Mathematics

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प्रश्न

Show that the function defined by f (x) = cos (x2) is a continuous function.

योग

उत्तर

Let f (x) = cos (x2).

Domian of f = R.

Let a be any arbitrary real number.

`lim_(x->a^-) f (x) = lim_(h->0) cos (a - h)^2 = cos a^2`

`lim_(x->a^+) f (x) = lim_(h->0) cos (a + h)^2 = cos a^2`

Also f (a) = cos a2

Thus, `lim_(x->a^-) f (x) = lim_(x->a^+) f (x) = f (a) AA a ∈ R`

∴ f (x) = cos(x2) is continuous at a ∀ a ∈ R.

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अध्याय 5: Continuity and Differentiability - Exercise 5.1 [पृष्ठ १६१]

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एनसीईआरटी Mathematics [English] Class 12
अध्याय 5 Continuity and Differentiability
Exercise 5.1 | Q 31 | पृष्ठ १६१

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