11th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 2 — 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 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) = −x2 + 6x − 5, find f(1).
Answer: 0
- Replace x with 1: −(1)2 + 6(1) − 5
- = 0
2.If f(x) = 4x2 + 6x + 3, find f(2).
Answer: 31
- Replace x with 2: 4(2)2 + 6(2) + 3
- = 31
3.If f(x) = 5x − 8, find f(−1).
Answer: −13
- Replace x with −1: 5(−1) − 8
- = −13
4.If f(x) = −3x2 − 6x + 8, find f(0).
Answer: 8
- Replace x with 0: −3(0)2 − 6(0) + 8
- = 8
5.If f(x) = −6x + 9, find f(−2).
Answer: 21
- Replace x with −2: −6(−2) + 9
- = 21
6.If f(x) = −6x + 7, find f(−3).
Answer: 25
- Replace x with −3: −6(−3) + 7
- = 25
7.If f(x) = −2x2 + 6x + 4, find f(0).
Answer: 4
- Replace x with 0: −2(0)2 + 6(0) + 4
- = 4
8.If f(x) = 2x − 6, find f(2).
Answer: −2
- Replace x with 2: 2(2) − 6
- = −2
9.If f(x) = 4x − 5, find f(5).
Answer: 15
- Replace x with 5: 4(5) − 5
- = 15
10.If f(x) = −x + 9, find f(5).
Answer: 4
- Replace x with 5: −(5) + 9
- = 4
11.If f(x) = −x2 − 6x − 5, find f(−3).
Answer: 4
- Replace x with −3: −(−3)2 − 6(−3) − 5
- = 4
12.If f(x) = −5x + 5, find f(−2).
Answer: 15
- Replace x with −2: −5(−2) + 5
- = 15
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