Year 11 Function Notation, Composites and Inverses Worksheet — Level 1 — Answers
Answer sheet with worked solutions for the Year 11 functions worksheet.
Success TutoringWorksheetsAnswer sheetYear 11 · Mathematics · FunctionsYear 11 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 − 6, find f(0).
Answer: −6
- Replace x with 0: −5(0) − 6
- = −6
2.If f(x) = 4x + 3, find f(5).
Answer: 23
- Replace x with 5: 4(5) + 3
- = 23
3.If f(x) = −3x2 + 6x + 7, find f(1).
Answer: 10
- Replace x with 1: −3(1)2 + 6(1) + 7
- = 10
4.If f(x) = −x2 − 3x − 8, find f(−4).
Answer: −12
- Replace x with −4: −(−4)2 − 3(−4) − 8
- = −12
5.If f(x) = 4x2 − 2x + 1, find f(3).
Answer: 31
- Replace x with 3: 4(3)2 − 2(3) + 1
- = 31
6.If f(x) = −3x2 − 5x − 3, find f(2).
Answer: −25
- Replace x with 2: −3(2)2 − 5(2) − 3
- = −25
7.If f(x) = −3x + 1, find f(−4).
Answer: 13
- Replace x with −4: −3(−4) + 1
- = 13
8.If f(x) = x − 7, find f(1).
Answer: −6
- Replace x with 1: (1) − 7
- = −6
9.If f(x) = x2 + x + 6, find f(−3).
Answer: 12
- Replace x with −3: (−3)2 + (−3) + 6
- = 12
10.If f(x) = −x2 + 4x + 8, find f(3).
Answer: 11
- Replace x with 3: −(3)2 + 4(3) + 8
- = 11
11.If f(x) = 2x + 7, find f(0).
Answer: 7
- Replace x with 0: 2(0) + 7
- = 7
12.If f(x) = 4x2 − x + 6, find f(1).
Answer: 9
- Replace x with 1: 4(1)2 − (1) + 6
- = 9
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