Year 10 Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 4 — 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 — 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) = 2x − 1, find f(−2).
Answer: −5
- Replace x with −2: 2(−2) − 1
- = −5
2.If f(x) = −x2 + 3x + 6, find f(−1).
Answer: 2
- Replace x with −1: −(−1)2 + 3(−1) + 6
- = 2
3.If f(x) = 3x2 − 2x + 1, find f(0).
Answer: 1
- Replace x with 0: 3(0)2 − 2(0) + 1
- = 1
4.If f(x) = x − 4, find f(−1).
Answer: −5
- Replace x with −1: (−1) − 4
- = −5
5.If f(x) = 2x + 6, find f(4).
Answer: 14
- Replace x with 4: 2(4) + 6
- = 14
6.If f(x) = 6x − 6, find f(1).
Answer: 0
- Replace x with 1: 6(1) − 6
- = 0
7.If f(x) = 3x, find f(2).
Answer: 6
- Replace x with 2: 3(2)
- = 6
8.If f(x) = 2x2 − 6x + 7, find f(−2).
Answer: 27
- Replace x with −2: 2(−2)2 − 6(−2) + 7
- = 27
9.If f(x) = −x2 + x − 8, find f(5).
Answer: −28
- Replace x with 5: −(5)2 + (5) − 8
- = −28
10.If f(x) = 3x2 − 2x + 5, find f(−1).
Answer: 10
- Replace x with −1: 3(−1)2 − 2(−1) + 5
- = 10
11.If f(x) = x + 7, find f(0).
Answer: 7
- Replace x with 0: (0) + 7
- = 7
12.If f(x) = 2x − 6, find f(5).
Answer: 4
- Replace x with 5: 2(5) − 6
- = 4
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