Year 12 Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 4 — 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 4 — 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) = −4x − 4, find f(1).
Answer: −8
- Replace x with 1: −4(1) − 4
- = −8
2.If f(x) = 4x2 − 2x − 3, find f(−2).
Answer: 17
- Replace x with −2: 4(−2)2 − 2(−2) − 3
- = 17
3.If f(x) = 4x2 − 6x + 5, find f(−3).
Answer: 59
- Replace x with −3: 4(−3)2 − 6(−3) + 5
- = 59
4.If f(x) = −2x2 + 4x − 7, find f(−1).
Answer: −13
- Replace x with −1: −2(−1)2 + 4(−1) − 7
- = −13
5.If f(x) = 2x + 1, find f(−1).
Answer: −1
- Replace x with −1: 2(−1) + 1
- = −1
6.If f(x) = 2x − 5, find f(−2).
Answer: −9
- Replace x with −2: 2(−2) − 5
- = −9
7.If f(x) = 3x + 3, find f(−3).
Answer: −6
- Replace x with −3: 3(−3) + 3
- = −6
8.If f(x) = −3x − 6, find f(−2).
Answer: 0
- Replace x with −2: −3(−2) − 6
- = 0
9.If f(x) = 3x − 7, find f(−4).
Answer: −19
- Replace x with −4: 3(−4) − 7
- = −19
10.If f(x) = −6x − 8, find f(−3).
Answer: 10
- Replace x with −3: −6(−3) − 8
- = 10
11.If f(x) = −3x + 7, find f(3).
Answer: −2
- Replace x with 3: −3(3) + 7
- = −2
12.If f(x) = 5x + 2, find f(−3).
Answer: −13
- Replace x with −3: 5(−3) + 2
- = −13
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