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Find the the values of c so that the function

f(x) = {( c² - x², x is < or equal to 3) ( x + c , x > 3)

1 Answer

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Final answer:

To make the piecewise function continuous at x = 3, we solve for c by setting c² - 9 equal to 3 + c, resulting in the quadratic equation c² - c - 12 = 0. Using the quadratic formula, we find the values of c are 4 and -3.

Step-by-step explanation:

The question asks us to find the values of c so that the piecewise function f(x) is continuous. A piecewise function is continuous at a point if both the left-hand limit and the right-hand limit as x approaches the point from either side are equal to the function's value at that point. In this case, we need the left-hand limit of c² - x² as x approaches 3 to equal the right-hand limit of x + c as x approaches 3.

Setting the two expressions equal to each other when x is equal to 3 gives us:

c² - (3)² = 3 + c

c² - 9 = 3 + c

c² - c - 12 = 0

This is a quadratic equation, and solving for c using the quadratic formula yields:

c = (-(-1) ± √((-1)^2 - 4(1)(-12)))/(2(1))

c = (1 ± √(1 + 48))/2

c = (1 ± √49)/2

c = (1 ± 7)/2

Therefore, the two possible values of c are:

  • c = (1 + 7)/2 = 4
  • c = (1 - 7)/2 = -3

User Matt Slavicek
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