11th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 4 — 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 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) = 2x − 8, find f(−2).
Answer: −12
- Replace x with −2: 2(−2) − 8
- = −12
2.If f(x) = −x2 − 2x + 8, find f(−4).
Answer: 0
- Replace x with −4: −(−4)2 − 2(−4) + 8
- = 0
3.If f(x) = −x2 − 4x − 8, find f(0).
Answer: −8
- Replace x with 0: −(0)2 − 4(0) − 8
- = −8
4.If f(x) = x2 − 6x − 5, find f(5).
Answer: −10
- Replace x with 5: (5)2 − 6(5) − 5
- = −10
5.If f(x) = −4x + 3, find f(−1).
Answer: 7
- Replace x with −1: −4(−1) + 3
- = 7
6.If f(x) = −6x − 9, find f(2).
Answer: −21
- Replace x with 2: −6(2) − 9
- = −21
7.If f(x) = −3x − 4, find f(−4).
Answer: 8
- Replace x with −4: −3(−4) − 4
- = 8
8.If f(x) = −4x + 6, find f(2).
Answer: −2
- Replace x with 2: −4(2) + 6
- = −2
9.If f(x) = 6x − 3, find f(−1).
Answer: −9
- Replace x with −1: 6(−1) − 3
- = −9
10.If f(x) = −6x − 3, find f(4).
Answer: −27
- Replace x with 4: −6(4) − 3
- = −27
11.If f(x) = x2 − 4, find f(−3).
Answer: 5
- Replace x with −3: (−3)2 − 4
- = 5
12.If f(x) = x − 6, find f(3).
Answer: −3
- Replace x with 3: (3) − 6
- = −3
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