11th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 11th Grade functions worksheet.
Success TutoringWorksheetsAnswer sheet11th Grade · Mathematics · Functions11th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 3 — 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) = −2x2 + 6x + 6, find f(−2).
Answer: −14
- Replace x with −2: −2(−2)2 + 6(−2) + 6
- = −14
2.If f(x) = 4x2 + 2x + 2, find f(3).
Answer: 44
- Replace x with 3: 4(3)2 + 2(3) + 2
- = 44
3.If f(x) = 2x2 − 4x + 1, find f(2).
Answer: 1
- Replace x with 2: 2(2)2 − 4(2) + 1
- = 1
4.If f(x) = −6x − 4, find f(1).
Answer: −10
- Replace x with 1: −6(1) − 4
- = −10
5.If f(x) = −6x + 7, find f(2).
Answer: −5
- Replace x with 2: −6(2) + 7
- = −5
6.If f(x) = 4x + 9, find f(−1).
Answer: 5
- Replace x with −1: 4(−1) + 9
- = 5
7.If f(x) = x2 + 4x + 6, find f(−3).
Answer: 3
- Replace x with −3: (−3)2 + 4(−3) + 6
- = 3
8.If f(x) = −2x2 − 4x + 9, find f(4).
Answer: −39
- Replace x with 4: −2(4)2 − 4(4) + 9
- = −39
9.If f(x) = 4x2 − 6x + 4, find f(−4).
Answer: 92
- Replace x with −4: 4(−4)2 − 6(−4) + 4
- = 92
10.If f(x) = −5x − 8, find f(2).
Answer: −18
- Replace x with 2: −5(2) − 8
- = −18
11.If f(x) = x2 − 5x + 2, find f(4).
Answer: −2
- Replace x with 4: (4)2 − 5(4) + 2
- = −2
12.If f(x) = −3x2 + 3x + 4, find f(5).
Answer: −56
- Replace x with 5: −3(5)2 + 3(5) + 4
- = −56
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