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(−3).
Answer: −21
- Replace x with −3: 5(−3) − 6
- = −21
2.If f(x) = 5x + 2, find f(−1).
Answer: −3
- Replace x with −1: 5(−1) + 2
- = −3
3.If f(x) = 2x + 9, find f(2).
Answer: 13
- Replace x with 2: 2(2) + 9
- = 13
4.If f(x) = −x2 + 3x + 3, find f(4).
Answer: −1
- Replace x with 4: −(4)2 + 3(4) + 3
- = −1
5.If f(x) = 6x, find f(−4).
Answer: −24
- Replace x with −4: 6(−4)
- = −24
6.If f(x) = 4x2 + 6x + 5, find f(4).
Answer: 93
- Replace x with 4: 4(4)2 + 6(4) + 5
- = 93
7.If f(x) = −2x + 6, find f(5).
Answer: −4
- Replace x with 5: −2(5) + 6
- = −4
8.If f(x) = 3x2 − 4x − 1, find f(1).
Answer: −2
- Replace x with 1: 3(1)2 − 4(1) − 1
- = −2
9.If f(x) = 2x + 7, find f(−3).
Answer: 1
- Replace x with −3: 2(−3) + 7
- = 1
10.If f(x) = −3x2 − 3x − 4, find f(−4).
Answer: −40
- Replace x with −4: −3(−4)2 − 3(−4) − 4
- = −40
11.If f(x) = −4x + 8, find f(−2).
Answer: 16
- Replace x with −2: −4(−2) + 8
- = 16
12.If f(x) = −5x − 6, find f(1).
Answer: −11
- Replace x with 1: −5(1) − 6
- = −11
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