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I am reading Andrew Browder's book: "Mathematical Analysis: An Introduction" ... ...
I am currently reading Chapter 3: Continuous Functions on Intervals and am currently focused on Section 3.1 Limits and Continuity ... ...
I need some help with the proof of Corollary 3.13 ...Corollary 3.13 reads as follows:View attachment 9520Can someone help me to prove that if $$f$$ is continuous then $$f^+ = \text{max} (f, 0)$$ is continuous ...My thoughts are as follows:If $$c$$ belongs to an interval where $$f$$ is positive then $$f^+$$ is continuous since $$f$$ is continuous ... further, if $$c$$ belongs to an interval where $$f$$ is negative then $$f^+$$ is continuous since $$g(x) = 0$$ is continuous ... but how do we construct a proof for those points where $$f(x)$$ crosses the $$x$$-axis ... ..
Help will be much appreciated ...
Peter
I am currently reading Chapter 3: Continuous Functions on Intervals and am currently focused on Section 3.1 Limits and Continuity ... ...
I need some help with the proof of Corollary 3.13 ...Corollary 3.13 reads as follows:View attachment 9520Can someone help me to prove that if $$f$$ is continuous then $$f^+ = \text{max} (f, 0)$$ is continuous ...My thoughts are as follows:If $$c$$ belongs to an interval where $$f$$ is positive then $$f^+$$ is continuous since $$f$$ is continuous ... further, if $$c$$ belongs to an interval where $$f$$ is negative then $$f^+$$ is continuous since $$g(x) = 0$$ is continuous ... but how do we construct a proof for those points where $$f(x)$$ crosses the $$x$$-axis ... ..
Help will be much appreciated ...
Peter
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