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Show that the function f(x) = |sin x + cos x| is continuous at x = π. - Mathematics

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प्रश्न

Show that the function f(x) = |sin x + cos x| is continuous at x = π.

बेरीज
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उत्तर

Given that f(x) = |sin x + cos x| at x = π

Put g(x) = sin x + cos x and h(x) = |x|

∴ h[g(x)] = h(sin x + cos x) = |sin x + cos x|

Now, g(x) = sin x + cos x is a continuous function since sin x and cos x are two continuous functions at x = π.

We know that every modulus function is a continuous function everywhere.

Hence, f(x) = |sin x + cos x| is continuous function at x = π. 

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पाठ 5: Continuity And Differentiability - Exercise [पृष्ठ १०९]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 5 Continuity And Differentiability
Exercise | Q 19 | पृष्ठ १०९

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