Skip to main content
Ch. 2 - Graphs and Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 79b

An equation that defines y as a function of x is given. Find ƒ(3). y+2x2=3-x

검증된 단계별 안내
1
Start with the given equation: \(y + 2x^{2} = 3 - x\).
Isolate \(y\) on one side to express it as a function of \(x\): subtract \$2x^{2}\( from both sides to get \)y = 3 - x - 2x^{2}$.
Rewrite the function notation as \(f(x) = 3 - x - 2x^{2}\) to clearly show \(y\) as a function of \(x\).
To find \(f(3)\), substitute \(x = 3\) into the function: \(f(3) = 3 - (3) - 2(3)^{2}\).
Simplify the expression step-by-step by calculating the powers and performing the arithmetic to find the value of \(f(3)\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
1m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Function Notation and Evaluation

Function notation, such as ƒ(x), represents a rule that assigns each input x to exactly one output y. Evaluating ƒ(3) means substituting x = 3 into the function's equation and calculating the corresponding y-value.
추천 영상:
4:26
Evaluating Composed Functions

Solving for y in Terms of x

To find ƒ(3), the equation must be rewritten to express y explicitly as a function of x. This involves isolating y on one side of the equation, often by performing algebraic operations like addition, subtraction, or division.
추천 영상:
5:02
Solving Logarithmic Equations

Substitution Method

After expressing y as a function of x, substitution involves replacing x with the given value (here, 3) to compute the specific output. This step is essential to find the function's value at a particular input.
추천 영상:
04:03
Choosing a Method to Solve Quadratics