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f+g may be a continuous function, if (a)...

`f+g` may be a continuous function, if (a) f is continuous and g is discontinuous

A

f is continuous and g is discontinuous (B) f is discontinuous and g is continuous

B

f is discontinuous and g is continuous

C

f and g are discontinuous

D

None of these

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To determine if \( f + g \) can be a continuous function when \( f \) is continuous and \( g \) is discontinuous, we can analyze the properties of continuous and discontinuous functions. ### Step-by-Step Solution: 1. **Understanding Continuity**: - A function \( f(x) \) is continuous at a point \( c \) if: \[ \lim_{x \to c} f(x) = f(c) \] - This means that as \( x \) approaches \( c \), \( f(x) \) approaches the value of \( f(c) \). 2. **Properties of Continuous Functions**: - If \( f \) and \( g \) are both continuous functions, then \( f + g \) is also continuous. - If either \( f \) or \( g \) is discontinuous, we need to analyze the behavior of their sum. 3. **Assuming \( f \) is Continuous**: - Let’s assume \( f(x) \) is continuous at \( x = c \). Therefore: \[ \lim_{x \to c} f(x) = f(c) \] 4. **Assuming \( g \) is Discontinuous**: - Let \( g(x) \) be discontinuous at \( x = c \). This means: \[ \lim_{x \to c} g(x) \neq g(c) \] - There could be different types of discontinuities (jump, infinite, removable, etc.). 5. **Analyzing \( f + g \)**: - We need to evaluate \( \lim_{x \to c} (f(x) + g(x)) \): \[ \lim_{x \to c} (f(x) + g(x)) = \lim_{x \to c} f(x) + \lim_{x \to c} g(x) \] - Since \( f(x) \) is continuous, we have: \[ \lim_{x \to c} f(x) = f(c) \] - However, since \( g(x) \) is discontinuous, \( \lim_{x \to c} g(x) \) does not equal \( g(c) \). 6. **Conclusion**: - Therefore, \( \lim_{x \to c} (f(x) + g(x)) \) does not equal \( f(c) + g(c) \). - This implies that \( f + g \) is discontinuous at \( x = c \). ### Final Conclusion: - Hence, \( f + g \) cannot be a continuous function if \( f \) is continuous and \( g \) is discontinuous. Therefore, the statement that \( f + g \) may be a continuous function under these conditions is false.
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