12th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 2 — Answers
Answer sheet with worked solutions for the 12th Grade functions worksheet.
Success TutoringWorksheetsAnswer sheet12th Grade · Mathematics · Functions12th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 2 — 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) = 3x − 8, find f(−1).
Answer: −11
- Replace x with −1: 3(−1) − 8
- = −11
2.If f(x) = −6x − 6, find f(1).
Answer: −12
- Replace x with 1: −6(1) − 6
- = −12
3.If f(x) = 2x − 6, find f(2).
Answer: −2
- Replace x with 2: 2(2) − 6
- = −2
4.If f(x) = 2x − 2, find f(5).
Answer: 8
- Replace x with 5: 2(5) − 2
- = 8
5.If f(x) = −3x2 − 6x + 9, find f(0).
Answer: 9
- Replace x with 0: −3(0)2 − 6(0) + 9
- = 9
6.If f(x) = 4x2 + 3x + 7, find f(−4).
Answer: 59
- Replace x with −4: 4(−4)2 + 3(−4) + 7
- = 59
7.If f(x) = −6x + 3, find f(−1).
Answer: 9
- Replace x with −1: −6(−1) + 3
- = 9
8.If f(x) = x + 8, find f(0).
Answer: 8
- Replace x with 0: (0) + 8
- = 8
9.If f(x) = −2x + 1, find f(−1).
Answer: 3
- Replace x with −1: −2(−1) + 1
- = 3
10.If f(x) = 4x − 6, find f(−4).
Answer: −22
- Replace x with −4: 4(−4) − 6
- = −22
11.If f(x) = −x + 2, find f(0).
Answer: 2
- Replace x with 0: −(0) + 2
- = 2
12.If f(x) = 2x2 + 5x + 6, find f(1).
Answer: 13
- Replace x with 1: 2(1)2 + 5(1) + 6
- = 13
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