Year 10 Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 10 functions worksheet.
Success TutoringWorksheetsAnswer sheetYear 10 · Mathematics · FunctionsYear 10 Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 2 — 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 − 3, find f(1).
Answer: −8
- Replace x with 1: −5(1) − 3
- = −8
2.If f(x) = 2x − 8, find f(0).
Answer: −8
- Replace x with 0: 2(0) − 8
- = −8
3.If f(x) = 2x2 + 4x + 4, find f(0).
Answer: 4
- Replace x with 0: 2(0)2 + 4(0) + 4
- = 4
4.If f(x) = 3x2 − x − 3, find f(−1).
Answer: 1
- Replace x with −1: 3(−1)2 − (−1) − 3
- = 1
5.If f(x) = 6x − 8, find f(−2).
Answer: −20
- Replace x with −2: 6(−2) − 8
- = −20
6.If f(x) = −3x2 − 5, find f(−3).
Answer: −32
- Replace x with −3: −3(−3)2 − 5
- = −32
7.If f(x) = 2x2 − 7, find f(−4).
Answer: 25
- Replace x with −4: 2(−4)2 − 7
- = 25
8.If f(x) = 3x + 1, find f(0).
Answer: 1
- Replace x with 0: 3(0) + 1
- = 1
9.If f(x) = 2x − 1, find f(5).
Answer: 9
- Replace x with 5: 2(5) − 1
- = 9
10.If f(x) = 5x − 8, find f(3).
Answer: 7
- Replace x with 3: 5(3) − 8
- = 7
11.If f(x) = −4x + 6, find f(2).
Answer: −2
- Replace x with 2: −4(2) + 6
- = −2
12.If f(x) = −3x2 − 9, find f(4).
Answer: −57
- Replace x with 4: −3(4)2 − 9
- = −57
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