11th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — 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 — 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 + 7, find f(1).
Answer: 5
- Replace x with 1: −2(1) + 7
- = 5
2.If f(x) = −x2 + 2x − 2, find f(4).
Answer: −10
- Replace x with 4: −(4)2 + 2(4) − 2
- = −10
3.If f(x) = x + 1, find f(5).
Answer: 6
- Replace x with 5: (5) + 1
- = 6
4.If f(x) = 3x2 + 4x + 5, find f(2).
Answer: 25
- Replace x with 2: 3(2)2 + 4(2) + 5
- = 25
5.If f(x) = 3x + 6, find f(−2).
Answer: 0
- Replace x with −2: 3(−2) + 6
- = 0
6.If f(x) = x2 + 3x − 6, find f(4).
Answer: 22
- Replace x with 4: (4)2 + 3(4) − 6
- = 22
7.If f(x) = −x2 + 5x + 3, find f(−2).
Answer: −11
- Replace x with −2: −(−2)2 + 5(−2) + 3
- = −11
8.If f(x) = 2x2 − 4x + 3, find f(−2).
Answer: 19
- Replace x with −2: 2(−2)2 − 4(−2) + 3
- = 19
9.If f(x) = −x2 + x + 3, find f(3).
Answer: −3
- Replace x with 3: −(3)2 + (3) + 3
- = −3
10.If f(x) = −4x + 1, find f(−2).
Answer: 9
- Replace x with −2: −4(−2) + 1
- = 9
11.If f(x) = 2x + 7, find f(−4).
Answer: −1
- Replace x with −4: 2(−4) + 7
- = −1
12.If f(x) = x2 − 2x − 9, find f(5).
Answer: 6
- Replace x with 5: (5)2 − 2(5) − 9
- = 6
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