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Help me with this one, please?

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Determine the value of "c" so that f(x) is continuous on the entire real line:

f(x) = { x-2, x<=5 AND cx-3, x>5 }

I'm not really sure what it's asking.

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  1. For f(x) to be continuous, it must have the same value for both equations at x = 5.

    If x &lt;= 5, f(x) = x-2, so f(5) = 3

    If x &gt; 5, f(x) = cx - 3, and c must be chosen so that the limit of f(x) as x approaches 5 from above is 3.  (f(5) is calculated from the first equation, so you must talk about the limit as x approaches 5 from above having the same value.)

    So if c*5 -3 = 3, then c = 6/5 and the second part of the function definition is

    If x &gt; 5, f(x) = 6x/5 - 3, which value approaches f(5) = 3 as x approaches 5 from above.


  2. Continuous= the function don&#039;t jump, then

    f(y)=f(y+e) (e=very tiny number)

    Solution:

    (x=5) x-2=cx-3 (x=5+0.00...01)

    5-2=5c-3

    c=6/5

  3. Start with

    x-2, x&lt;=5 (since it has the equals sign included)

    when x=5,

    5-2=3

    so then for

    cx - 3  = 3 when x=5

    so then

    c*5 - 3 = 3

    5c - 3 = 3

    5c = 6

    c = 6/5


  4. For the solution to be continuous, there can be no break in the solution. The question is simply this: &quot;Where could f(x) break?&quot; Since each piece (x-2 and cx-3) are linear, they are both continuous throughout. Therefore, the answer is also simple: &quot;Where x-2 ends and cx-3 begins is the only place there could be discontinuity.&quot;

    So, you must make sure that there is no break at the point where x=5 (the endpoint of both lines). So, x-2 must equal cx-3 at x=5 or:

    5-2 = 5c-3

    3 = 5c-3

    6 = 5c

    c = 6/5

    so f(x) = { x-2, x&lt;=5 AND 6c/5-3, x&gt;5 }

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