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Find the constant a such that the function is continuous on the entire real line: g(x) = x² - a²x - a, x ≠ a², x = a.

User Chadbag
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Final answer:

The constant 'a' required for the function g(x) to be continuous on the entire real line is 0, as it makes the limit and the function's value at x = a² consistent.

Step-by-step explanation:

To find the constant a that makes the function g(x) = x² - a²x - a continuous on the entire real line, we need to ensure that the function is defined at x = a² and that there is no jump discontinuity at that point. Since continuous functions have limits that equal the function's value at the point, we must find a such that ℝ

limx → a²g(x) = g(a²).

Because the function g(x) is not defined at x = a² in the original statement, we will replace x with a² and therefore:

g(a²) = (a²)² - a²(a²) - a.

This simplifies to:

g(a²) = a⁴ - a⁴ - a = -a.

Now that we have the value of the function at x = a², we set the limit equal to this value:

limx → a²g(x) = -a.

As x approaches a², the function becomes:

g(x) = x² - a²x - a, which for the limit as x approaches a² simplifies to:

x² - a²x - a.

Now we equate the limit to the function's value at x = a²:

(a²)² - a²(a²) = -a

a⁴ - a⁴ = -a

This results in 0 = -a. Therefore, the constant a is 0.

User Markus Meyer
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