Functions & Relations
Is {(1,2), (2,3), (1,4)} a function?
No
solve
2x - 3 = 7
x = 5
Find slope of line through (2,3) and (4,7)
m = 2
solve
x + 5 < 10
x < 5
write in standard form of y = 2x – 4
2x – y = 4
solve f(x) = 2x – 1 for x = -3
f(x) = -7
solve
3(x – 1) = 2x + 4
x = 7
Graph y = 2x – 3: What is the y-intercept?
y = -3
solve
2x – 3 ≥ 5
x ≥ 4
What is the slope of y = –3x + 7?
m = –3
What is the domain of f(x) = 1/(x–2)?
All real x ≠ 2
solve
5x + 2 = 3x – 6
x = -4
Graph x = -2: What kind of line is this?
Vertical line
solve
x – 2 ≤ 3
≤ 5
Find x if |x – 4| = 9
x = 13 or -5
What is the range of f(x) = x² + 1?
y ≥ 1
solve
4(x + 3) = 2x – 8
x = -10
Find the x-intercept of 3x + 2y = 6
x = 2
solve
Write in interval notation 1 < x ≤ 4
Interval: (1, 4]
Evaluate f(x) = √x at x = 25
f(x) = 5
Use the vertical line test. What does it check for?
Whether a graph represents a function
solve
6 – 2(x – 1) = 4x
x = 1/3
Graph y = 5: What kind of line is this?
Horizontal line
solve
|x + 3| ≥ 7
x ≤ -10 or x ≥ 4
What is the opposite reciprocal of -2?
1/2