12th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — 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 — 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) = 6x + 1, find f(−4).
Answer: −23
- Replace x with −4: 6(−4) + 1
- = −23
2.If f(x) = 4x2 − 6x − 3, find f(5).
Answer: 67
- Replace x with 5: 4(5)2 − 6(5) − 3
- = 67
3.If f(x) = 2x2 − 3x + 1, find f(−1).
Answer: 6
- Replace x with −1: 2(−1)2 − 3(−1) + 1
- = 6
4.If f(x) = x + 6, find f(4).
Answer: 10
- Replace x with 4: (4) + 6
- = 10
5.If f(x) = −4x − 1, find f(0).
Answer: −1
- Replace x with 0: −4(0) − 1
- = −1
6.If f(x) = x − 8, find f(−1).
Answer: −9
- Replace x with −1: (−1) − 8
- = −9
7.If f(x) = −x2 − 5x − 2, find f(−4).
Answer: 2
- Replace x with −4: −(−4)2 − 5(−4) − 2
- = 2
8.If f(x) = −2x − 3, find f(−1).
Answer: −1
- Replace x with −1: −2(−1) − 3
- = −1
9.If f(x) = −6x + 8, find f(−3).
Answer: 26
- Replace x with −3: −6(−3) + 8
- = 26
10.If f(x) = −x2 + 6x + 2, find f(−1).
Answer: −5
- Replace x with −1: −(−1)2 + 6(−1) + 2
- = −5
11.If f(x) = 4x + 5, find f(−1).
Answer: 1
- Replace x with −1: 4(−1) + 5
- = 1
12.If f(x) = −5x + 4, find f(−3).
Answer: 19
- Replace x with −3: −5(−3) + 4
- = 19
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