10th Grade Function Notation, Composites and Inverses Worksheet — Level 1 — Practice Set 2 — 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 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 + 4x − 7, find f(0).
Answer: −7
- Replace x with 0: (0)2 + 4(0) − 7
- = −7
2.If f(x) = 3x2 + x + 2, find f(2).
Answer: 16
- Replace x with 2: 3(2)2 + (2) + 2
- = 16
3.If f(x) = 4x2 − 3x + 8, find f(5).
Answer: 93
- Replace x with 5: 4(5)2 − 3(5) + 8
- = 93
4.If f(x) = −x2 + 6x + 9, find f(4).
Answer: 17
- Replace x with 4: −(4)2 + 6(4) + 9
- = 17
5.If f(x) = 2x2 − 6x − 4, find f(−1).
Answer: 4
- Replace x with −1: 2(−1)2 − 6(−1) − 4
- = 4
6.If f(x) = 2x2 + 3x + 4, find f(1).
Answer: 9
- Replace x with 1: 2(1)2 + 3(1) + 4
- = 9
7.If f(x) = 3x + 1, find f(−1).
Answer: −2
- Replace x with −1: 3(−1) + 1
- = −2
8.If f(x) = 3x2 − 6, find f(−1).
Answer: −3
- Replace x with −1: 3(−1)2 − 6
- = −3
9.If f(x) = −3x2 + 2x, find f(−4).
Answer: −56
- Replace x with −4: −3(−4)2 + 2(−4)
- = −56
10.If f(x) = 4x − 1, find f(−1).
Answer: −5
- Replace x with −1: 4(−1) − 1
- = −5
11.If f(x) = −3x2 − 4x + 5, find f(−4).
Answer: −27
- Replace x with −4: −3(−4)2 − 4(−4) + 5
- = −27
12.If f(x) = −3x2 − x − 3, find f(2).
Answer: −17
- Replace x with 2: −3(2)2 − (2) − 3
- = −17
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