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Find the x - and y -intercepts of the rational function. r(x)=x³+8 / x²+4

User Kapobajza
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Final answer:

The rational function r(x)=(x³+8)/(x²+4) has no x-intercept because the numerator cannot be zero without the denominator also being zero. The y-intercept is found by setting x to zero, which gives the point (0, 2).

Step-by-step explanation:

To find the x-intercept and y-intercept of the rational function r(x) = (x³ + 8) / (x² + 4), we must set each variable to zero in turn and solve for the other.

Finding the x-intercept:

For the x-intercept, the value of y (which is r(x) in this case) must be zero:

0 = (x³ + 8) / (x² + 4)

This implies that x³ + 8 = 0, so x = -2. However, we must consider the domain of the rational function and note that x = -2 is not an intercept since the denominator (x² + 4) doesn't equal zero at x = -2. Thus, we realize that there is no x-intercept for this function because the numerator cannot be zero without making the denominator zero as well.

Finding the y-intercept:

To find the y-intercept, we substitute x = 0 into the function:

r(0) = (0³ + 8) / (0² + 4) = 8 / 4 = 2

The y-intercept of the function is at the point (0, 2).

User Tegancp
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