Year 12 Function Notation, Composites and Inverses Worksheet — Level 1 — 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 — 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) = 2x − 1, find f(−4).
Answer: −9
- Replace x with −4: 2(−4) − 1
- = −9
2.If f(x) = 6x − 7, find f(3).
Answer: 11
- Replace x with 3: 6(3) − 7
- = 11
3.If f(x) = −x2 + 6x − 2, find f(−1).
Answer: −9
- Replace x with −1: −(−1)2 + 6(−1) − 2
- = −9
4.If f(x) = 4x + 4, find f(−2).
Answer: −4
- Replace x with −2: 4(−2) + 4
- = −4
5.If f(x) = 3x − 1, find f(1).
Answer: 2
- Replace x with 1: 3(1) − 1
- = 2
6.If f(x) = −x2 − x + 5, find f(−4).
Answer: −7
- Replace x with −4: −(−4)2 − (−4) + 5
- = −7
7.If f(x) = 3x2 − 6x + 5, find f(3).
Answer: 14
- Replace x with 3: 3(3)2 − 6(3) + 5
- = 14
8.If f(x) = −x + 3, find f(−4).
Answer: 7
- Replace x with −4: −(−4) + 3
- = 7
9.If f(x) = 2x2 + 4x + 4, find f(4).
Answer: 52
- Replace x with 4: 2(4)2 + 4(4) + 4
- = 52
10.If f(x) = −2x2 + 6x, find f(−3).
Answer: −36
- Replace x with −3: −2(−3)2 + 6(−3)
- = −36
11.If f(x) = 2x2 + 9, find f(0).
Answer: 9
- Replace x with 0: 2(0)2 + 9
- = 9
12.If f(x) = 3x2 − 4x + 6, find f(0).
Answer: 6
- Replace x with 0: 3(0)2 − 4(0) + 6
- = 6
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