10th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 4 — Answers
Answer sheet with worked solutions for the 10th Grade functions worksheet.
Success TutoringWorksheetsAnswer sheet10th Grade · Mathematics · Functions10th 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) = −5x − 1, find f(1).
Answer: −6
- Replace x with 1: −5(1) − 1
- = −6
2.If f(x) = x2 + 3x − 8, find f(4).
Answer: 20
- Replace x with 4: (4)2 + 3(4) − 8
- = 20
3.If f(x) = −2x − 5, find f(0).
Answer: −5
- Replace x with 0: −2(0) − 5
- = −5
4.If f(x) = 2x2 + 3x + 4, find f(5).
Answer: 69
- Replace x with 5: 2(5)2 + 3(5) + 4
- = 69
5.If f(x) = −3x2 + x, find f(3).
Answer: −24
- Replace x with 3: −3(3)2 + (3)
- = −24
6.If f(x) = −x2 + 5x + 3, find f(−4).
Answer: −33
- Replace x with −4: −(−4)2 + 5(−4) + 3
- = −33
7.If f(x) = −2x2 − 6x, find f(0).
Answer: 0
- Replace x with 0: −2(0)2 − 6(0)
- = 0
8.If f(x) = x2 − 6x + 9, find f(5).
Answer: 4
- Replace x with 5: (5)2 − 6(5) + 9
- = 4
9.If f(x) = −3x − 5, find f(1).
Answer: −8
- Replace x with 1: −3(1) − 5
- = −8
10.If f(x) = −x + 1, find f(1).
Answer: 0
- Replace x with 1: −(1) + 1
- = 0
11.If f(x) = −2x2 + 4x − 4, find f(−4).
Answer: −52
- Replace x with −4: −2(−4)2 + 4(−4) − 4
- = −52
12.If f(x) = 2x2 + 5x − 4, find f(5).
Answer: 71
- Replace x with 5: 2(5)2 + 5(5) − 4
- = 71
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