Year 13 Function Notation, Composites and Inverses Worksheet — Level 1 — Answers
Answer sheet with worked solutions for the Year 13 functions worksheet.
Success TutoringWorksheetsAnswer sheetYear 13 · Mathematics · FunctionsYear 13 Function Notation, Composites and Inverses Worksheet — Level 1 — Answers
f(x) notation means "the value of the function at x". For a composite, substitute the inner function into the outer one. For an inverse, swap x and y and solve for y.
1.If f(x) = −5x − 1, find f(1).
Answer: −6
- Replace x with 1: −5(1) − 1
- = −6
2.If f(x) = −6x − 9, find f(0).
Answer: −9
- Replace x with 0: −6(0) − 9
- = −9
3.If f(x) = −4x + 6, find f(0).
Answer: 6
- Replace x with 0: −4(0) + 6
- = 6
4.If f(x) = 6x + 5, find f(1).
Answer: 11
- Replace x with 1: 6(1) + 5
- = 11
5.If f(x) = 2x + 1, find f(−4).
Answer: −7
- Replace x with −4: 2(−4) + 1
- = −7
6.If f(x) = 4x2 + 9, find f(−1).
Answer: 13
- Replace x with −1: 4(−1)2 + 9
- = 13
7.If f(x) = 2x + 9, find f(3).
Answer: 15
- Replace x with 3: 2(3) + 9
- = 15
8.If f(x) = −2x2 + 6x + 5, find f(2).
Answer: 9
- Replace x with 2: −2(2)2 + 6(2) + 5
- = 9
9.If f(x) = 5x − 3, find f(5).
Answer: 22
- Replace x with 5: 5(5) − 3
- = 22
10.If f(x) = 2x + 1, find f(−2).
Answer: −3
- Replace x with −2: 2(−2) + 1
- = −3
11.If f(x) = x2 − 5, find f(3).
Answer: 4
- Replace x with 3: (3)2 − 5
- = 4
12.If f(x) = 5x − 3, find f(2).
Answer: 7
- Replace x with 2: 5(2) − 3
- = 7
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