Sketch the graphs of the functions - Calculus question

Mary4ever
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Homework Statement


Sketch the graphs of the functions. Indicate intervals on which the function is increasing, decreasing, concave up, or concave down; indicate relative maximum points, relative minimum points, points of inflection, horizontal asymptotes, vertical asymptotes, symmetry, and those intercepts that can be obtained conveniently:

Homework Equations


y=x/((2x-1)^3)


The Attempt at a Solution


I have a solution, but it involves a graph, which I cannot put here
 
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Mary4ever said:

Homework Statement


Sketch the graphs of the functions. Indicate intervals on which the function is increasing, decreasing, concave up, or concave down; indicate relative maximum points, relative minimum points, points of inflection, horizontal asymptotes, vertical asymptotes, symmetry, and those intercepts that can be obtained conveniently:

Homework Equations


y=x/((2x-1)^3)

The Attempt at a Solution


I have a solution, but it involves a graph, which I cannot put here
Hello Mary4ever. Welcome to PF !

That makes it difficult to say whether your solution is correct or not.

Can you give your results for: intervals on which the function is increasing, decreasing, concave up, or concave down; indicate relative maximum points, relative minimum points, points of inflection, horizontal asymptotes, vertical asymptotes, symmetry, and those intercepts that can be obtained conveniently ?
 
For relative maxima and minima,

f'(x) = 0 gives e^x = e^{-x}, which happens when x=0, only.

f''(0) =f(0) = 1

and so x=0 is a minimum. It is also an absolute minimum, because f is increasing for
x>0 and decreasing for x<0.

f''(x) > 0 for all x and so concave up everywhere, no points of inflection.

Please let me know if this is correct, and please let me know the asymptotes and how to sketch the graph. Thank you
 
Mary4ever said:
For relative maxima and minima,

f'(x) = 0 gives e^x = e^{-x}, which happens when x=0, only.
Where does ex come into this problem?

Your function is f(x) = x/(2x - 1)3.
Mary4ever said:
f''(0) =f(0) = 1

and so x=0 is a minimum. It is also an absolute minimum, because f is increasing for
x>0 and decreasing for x<0.

f''(x) > 0 for all x and so concave up everywhere, no points of inflection.

Please let me know if this is correct, and please let me know the asymptotes and how to sketch the graph. Thank you
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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