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Find the value of c that makes the function continuous.

f(x)= 2x+9 for x≤3
-4x+c for x>3

User Jvarela
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1 Answer

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Final answer:

The value of c that makes the function continuous is 27, as determined by setting the left-hand and right-hand expressions for f(x) equal at the point x = 3.

Step-by-step explanation:

To find the value of c that makes the function continuous, we consider the given piecewise function:

  • f(x) = 2x + 9 for x ≤3
  • f(x) = -4x + c for x > 3

A function is continuous at a point if the left-hand limit, the right-hand limit, and the value of the function at that point are all equal. Since we want the function to be continuous at x = 3, we set the expressions for f(x) from the left and right of x = 3 equal to each other:

2(3) + 9 = -4(3) + c

By calculating both sides, we find:

6 + 9 = -12 + c

This simplifies to:

15 = -12 + c

Therefore, adding 12 to both sides gives us:

c = 27

So, c = 27 is the value that ensures the function is continuous at x = 3.

User Manuel Riviere
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