12th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 4 — 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 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) = 3x2 − 6x + 1, find f(0).
Answer: 1
- Replace x with 0: 3(0)2 − 6(0) + 1
- = 1
2.If f(x) = −2x2 − 6x − 2, find f(−1).
Answer: 2
- Replace x with −1: −2(−1)2 − 6(−1) − 2
- = 2
3.If f(x) = 2x + 6, find f(3).
Answer: 12
- Replace x with 3: 2(3) + 6
- = 12
4.If f(x) = −6x − 6, find f(−2).
Answer: 6
- Replace x with −2: −6(−2) − 6
- = 6
5.If f(x) = 4x2 + 2x − 6, find f(1).
Answer: 0
- Replace x with 1: 4(1)2 + 2(1) − 6
- = 0
6.If f(x) = 6x + 9, find f(4).
Answer: 33
- Replace x with 4: 6(4) + 9
- = 33
7.If f(x) = 3x + 5, find f(5).
Answer: 20
- Replace x with 5: 3(5) + 5
- = 20
8.If f(x) = −2x2 + 5x + 8, find f(−1).
Answer: 1
- Replace x with −1: −2(−1)2 + 5(−1) + 8
- = 1
9.If f(x) = 4x2 − 6x + 5, find f(4).
Answer: 45
- Replace x with 4: 4(4)2 − 6(4) + 5
- = 45
10.If f(x) = −3x2 + 6x + 4, find f(−4).
Answer: −68
- Replace x with −4: −3(−4)2 + 6(−4) + 4
- = −68
11.If f(x) = x2 + 2x + 1, find f(0).
Answer: 1
- Replace x with 0: (0)2 + 2(0) + 1
- = 1
12.If f(x) = x2 + 5x − 7, find f(−4).
Answer: −11
- Replace x with −4: (−4)2 + 5(−4) − 7
- = −11
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