Year 12 Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 12 functions worksheet.
Success TutoringWorksheetsAnswer sheetYear 12 · Mathematics · FunctionsYear 12 Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 3 — 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) = −x2 − 4x + 4, find f(0).
Answer: 4
- Replace x with 0: −(0)2 − 4(0) + 4
- = 4
2.If f(x) = −4x + 3, find f(1).
Answer: −1
- Replace x with 1: −4(1) + 3
- = −1
3.If f(x) = 4x − 2, find f(5).
Answer: 18
- Replace x with 5: 4(5) − 2
- = 18
4.If f(x) = 3x + 4, find f(4).
Answer: 16
- Replace x with 4: 3(4) + 4
- = 16
5.If f(x) = −2x − 3, find f(2).
Answer: −7
- Replace x with 2: −2(2) − 3
- = −7
6.If f(x) = −2x + 3, find f(−2).
Answer: 7
- Replace x with −2: −2(−2) + 3
- = 7
7.If f(x) = 3x + 2, find f(4).
Answer: 14
- Replace x with 4: 3(4) + 2
- = 14
8.If f(x) = 2x + 6, find f(0).
Answer: 6
- Replace x with 0: 2(0) + 6
- = 6
9.If f(x) = 5x − 5, find f(0).
Answer: −5
- Replace x with 0: 5(0) − 5
- = −5
10.If f(x) = 2x + 4, find f(1).
Answer: 6
- Replace x with 1: 2(1) + 4
- = 6
11.If f(x) = −3x2 + 6x + 6, find f(−3).
Answer: −39
- Replace x with −3: −3(−3)2 + 6(−3) + 6
- = −39
12.If f(x) = 2x + 2, find f(−1).
Answer: 0
- Replace x with −1: 2(−1) + 2
- = 0
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