Construct a piecewise function f(x)

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SUMMARY

The discussion focuses on constructing a piecewise function f(x) that meets specific mathematical criteria: it must be concave down on (-∞, 5), concave up on (5, ∞), and increasing over the entire domain. The function must also have a non-zero slope at the inflection point x = 5, where f(5) = 11 and f'(5) = 6. Participants suggest using two candidate functions, adjusting their derivatives and values through vertical and horizontal shifts to satisfy these conditions.

PREREQUISITES
  • Understanding of piecewise functions
  • Knowledge of concavity and inflection points
  • Familiarity with derivatives and their geometric interpretations
  • Ability to manipulate function equations through transformations
NEXT STEPS
  • Study the properties of concave functions and their derivatives
  • Learn how to construct piecewise functions with specific characteristics
  • Explore the concept of inflection points and their significance in calculus
  • Practice shifting graphs of functions to meet defined criteria
USEFUL FOR

Students in calculus, mathematics educators, and anyone interested in advanced function construction and analysis.

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Homework Statement


Construct a piecewise function f(x) such that the following conditions are satisfied:

Concave down on ( - infinity, 5)
Concave up on (5, infinity)
increasing over ( -infinity,infinity)
Nonzero- sloped tangent line at the point of inflection x = 5
f(5) = 11 (continuous at x = 5)
f ' (5) =6

The Attempt at a Solution


I really don't know what I should do to get started. My teacher assigned this as a homework problem without going over anything related to this. I could draw a graph to easily satisfy the given conditions, but I don't know how to find the equations of the curves I drew.If you could point me in the right direction I would really appreciate it.
 
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The condition f(5) = 11 is not a problem. Geometrically, we can shift any graph we find up or down by the right amount to fulfill this. In equations, this is just adding a constant to the end of whatever piecewise function we define. (Why?)

The condition of non-zero sloped tangent line at x = 5 is redundant, because f'(5) = 6.

What is an increasing concave up function? What is an increasing concave down function? Even if you cannot find one that is increasing everywhere, can you find one that is increasing over part of its domain? You can perhaps chop it off where you need it.

In particular, if your two candidate functions off of which you will take pieces are f(x) and g(x). Find when f'(x) = 6 and g'(x) = 6. Shift the graph left or right (how do you do this?) until both have derivative 6 at x = 5. Shift the graph up or down until both are equal to 11 at x = 5.
 

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