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Division by zero is not defined. This means that the denominator cannot be zero.
Domain: All real numbers except x=0 and x=2
Points of Discontinuity: Non-removable at x=0 and x=2
x-intercepts: None
y-intercept: None
We want to find the domain, points of discontinuity, and x- and y-intercepts of the graph of the given rational function. We also want to determine whether the discontinuities are removable or non-removable. Let's do these things one at a time.
Consider the given function.
y=2x^2+5/x^2-2x
To find the domain, we will start by factoring the denominator.
We have fully factored the denominator. y=2x^2+5/x(x- 2) Recall that division by zero is not defined. Therefore, the rational function is undefined where x- 2=0 and where x=0. ccc x- 2=0 & and & x=0 ⇕ & & ⇕ x= 2 & and & x= 0 This means that neither x= 2 nor x= 0 are included in the domain. Domain All real numbers except x= 2 and x= 0
If a real number a is not in the domain of a function, then the function has a point of discontinuity at x=a. Since the domain is all real numbers except x= 2, and x= 0, we can write the points of discontinuity of our function. Points of Discontinuity x= 2 and x= 0 The numerator is already factored, but we cannot cancel out common factors between the numerator and the denominator. Therefore, every point of discontinuity is a non-removable discontinuity.
The intercepts of a function are the points where the graph intersects the axes. Let's calculate the intercepts of the given function, if there are any.
The x-intercepts of a function are the points where the graph intersects the x-axis. At these points, the value of the y-coordinate is zero. Therefore, to find the x-intercepts, we have to substitute 0 for y in the function rule and solve for x.
y= 0
LHS * (x^2-2x)=RHS* (x^2-2x)
LHS-=RHS-
.LHS /2.=.RHS /2.
Rearrange equation
Notice that x^2 cannot have negative value. Therefore, there are no x-intercepts.
The y-intercept of a function is the point where the graph intersects the y-axis. At this point, the value of the x-coordinate is zero. Since x=0 is not in the domain of the function, there is no y-intercept.