MHB True or False Integral Calculus Question #3

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The statement is false because squaring the negative function f(x) transforms it into a positive function, which is increasing over the interval [0, 1]. As a result, right-hand Riemann sums for positive, increasing functions yield overestimates of the integral. Therefore, the assertion that right-hand sums always provide an underestimate for the integral of (f(x))^2 is incorrect. The discussion highlights the importance of understanding how transformations of functions affect Riemann sums. Ultimately, the conclusion is that right-hand sums will overestimate the integral in this case.
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True or False: If $f(x)$ is a negative function that satisfies $f'(x) > 0$ for $0 \le x \le 1$, then the right hand sums always yield an underestimate of $\int_{0}^{1} (f(x))^2\,dx$.

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Would it be true since right hand Riemann sums for a negative, increasing function will always produce an underestimate for the integral, so it doesn't really matter if the entire "function" we're dealing with is squared?
 
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$(f(x))^2\ge0$
 
Or... would it be that squaring $f(x)$ will turn $f(x)$ into a positive function from a negative function, so the statement is going to be false because taking the right Riemann sum will still give you an overestimate for positive, increasing functions?
 
Yeah, OK. So, in that case, it becomes a positive, increasing function, so it's an overestimate, right?
 
That's right.
 

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