I'll solve the problem in the image, which is about evaluating rational functions. Let me go through each part step by step.
Part 1: Evaluate each function at the specified value
Problem 1: f(x) = (x+1)/(x-3); x = -1
- Substitute x = -1 into the function: f(-1) = (-1+1)/(-1-3) = 0/(-4) = 0
Problem 2: f(x) = (x²-2x)/(x-2); x = 4
- Substitute x = 4 into the function: f(4) = (4²-2×4)/(4-2) = (16-8)/2 = 8/2 = 4
Problem 3: f(x) = (5x-3)/(2x+1); x = 2
- Substitute x = 2 into the function: f(2) = (5×2-3)/(2×2+1) = (10-3)/(4+1) = 7/5
Problem 4: f(x) = (3x+1)/(x-4); x = 4
- Substitute x = 4 into the function: f(4) = (3×4+1)/(4-4) = (12+1)/0 = 13/0
- This is undefined because we cannot divide by zero.
Part 2: Evaluate each function
Problem 5: f(x) = (x²-4)/(x-2); for x ≠ 2
- We can factor the numerator: x²-4 = (x-2)(x+2)
- So f(x) = ((x-2)(x+2))/(x-2)
- For x ≠ 2, we can cancel (x-2) from numerator and denominator: f(x) = x+2
- So for any x ≠ 2, f(x) = x+2
Problem 6: f(x) = (8x)/(x-1); for x ≠ 1
- This function is already simplified.
- For any x ≠ 1, f(x) = 8x/(x-1)
Problem 7: f(x) = 1/(x+2); for x ≠ -2
- This function is already simplified.
- For any x ≠ -2, f(x) = 1/(x+2)
Problem 8: f(x) = (x+3)/(x(x-1)); for x ≠ 0, 1
- This function is already simplified.
- For any x ≠ 0, 1, f(x) = (x+3)/(x(x-1))
Part 3: What is the value of x that makes f(x) = (x²-4)/(x-2) undefined?
The function f(x) = (x²-4)/(x-2) is undefined when the denominator equals zero.
- Set the denominator equal to zero: x-2 = 0
- Solve for x: x = 2
Therefore, the function is undefined when x = 2.
Looking at the multiple choice options:
a) -∞
b) 0
c) 2
d) -2
The correct answer is
c) 2.
This matches with what we found in Problem 5, where we noted that x ≠ 2 because the function would be undefined at that point.
Parent Tip: Review the logic above to help your child master the concept of evaluating linear functions worksheet.