Year 10 Function Notation, Composites and Inverses Worksheet — Level 1 — Answers
Answer sheet with worked solutions for the Year 10 functions worksheet.
Success TutoringWorksheetsAnswer sheetYear 10 · Mathematics · FunctionsYear 10 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, find f(−2).
Answer: 4
- Replace x with −2: −2(−2)
- = 4
2.If f(x) = −6x − 9, find f(5).
Answer: −39
- Replace x with 5: −6(5) − 9
- = −39
3.If f(x) = x2 − 5x + 2, find f(−3).
Answer: 26
- Replace x with −3: (−3)2 − 5(−3) + 2
- = 26
4.If f(x) = 3x2 − 4x + 4, find f(3).
Answer: 19
- Replace x with 3: 3(3)2 − 4(3) + 4
- = 19
5.If f(x) = −3x2 − x − 9, find f(−3).
Answer: −33
- Replace x with −3: −3(−3)2 − (−3) − 9
- = −33
6.If f(x) = −x + 4, find f(1).
Answer: 3
- Replace x with 1: −(1) + 4
- = 3
7.If f(x) = 5x + 1, find f(4).
Answer: 21
- Replace x with 4: 5(4) + 1
- = 21
8.If f(x) = 4x − 4, find f(−1).
Answer: −8
- Replace x with −1: 4(−1) − 4
- = −8
9.If f(x) = −6x − 8, find f(0).
Answer: −8
- Replace x with 0: −6(0) − 8
- = −8
10.If f(x) = −x − 6, find f(−1).
Answer: −5
- Replace x with −1: −(−1) − 6
- = −5
11.If f(x) = 2x + 2, find f(5).
Answer: 12
- Replace x with 5: 2(5) + 2
- = 12
12.If f(x) = −x2 − 4x + 2, find f(2).
Answer: −10
- Replace x with 2: −(2)2 − 4(2) + 2
- = −10
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