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Ch. 3 - Derivatives
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 75a

{Use of Tech} The Witch of Agnesi The graph of y = a3 / (x2 + a2), where a is a constant, is called the witch of Agnesi (named after the 18th-century Italian mathematician Maria Agnesi).
Let a = 3 and find an equation of the line tangent to y = 27 / (x2 + 9) at x = 2.

검증된 단계별 안내
1
Step 1: Substitute a = 3 into the given function to get y = \(\frac{27}{x^2 + 9}\).
Step 2: Find the derivative of y with respect to x, which will give us the slope of the tangent line. Use the quotient rule: if y = \(\frac{u}{v}\), then y' = \(\frac{u'v - uv'}{v^2}\). Here, u = 27 and v = x^2 + 9.
Step 3: Calculate the derivative: u' = 0 (since 27 is a constant) and v' = 2x. Substitute these into the quotient rule formula to find y'.
Step 4: Evaluate the derivative at x = 2 to find the slope of the tangent line at this point.
Step 5: Use the point-slope form of a line, y - y_1 = m(x - x_1), where m is the slope found in Step 4 and (x_1, y_1) is the point on the curve at x = 2, to write the equation of the tangent line.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
8m

주요 개념

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

Tangent Line

A tangent line to a curve at a given point is a straight line that touches the curve at that point without crossing it. The slope of the tangent line is determined by the derivative of the function at that point. To find the equation of the tangent line, one needs the point of tangency and the slope, which can be calculated using the derivative.
추천 영상:
가이드 코스
05:13
Slopes of Tangent Lines

Derivative

The derivative of a function measures how the function's output value changes as its input value changes. It is defined as the limit of the average rate of change of the function over an interval as the interval approaches zero. In practical terms, the derivative provides the slope of the tangent line to the graph of the function at any given point.
추천 영상:

Function Evaluation

Function evaluation involves substituting a specific value into a function to determine its output. In this context, evaluating the function y = 27 / (x² + 9) at x = 2 is necessary to find the y-coordinate of the point where the tangent line touches the curve. This step is crucial for establishing the point of tangency needed to write the equation of the tangent line.
추천 영상:
가이드 코스
4:26
Evaluating Composed Functions