Skip to main content
Ch. 7 - Logarithmic, Exponential Functions, and Hyperbolic Functions
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243당신이 사용하는 게 아니라요?교과서 변경
7장, 문제 7.3.2

Sketch the graphs of y = cosh x, y = sinh x, and y = tanh x (include asymptotes), and state whether each function is even, odd, or neither.

검증된 단계별 안내
1
Recall the definitions of the hyperbolic functions: \(\cosh x = \frac{e^{x} + e^{-x}}{2}\), \(\sinh x = \frac{e^{x} - e^{-x}}{2}\), and \(\tanh x = \frac{\sinh x}{\cosh x} = \frac{e^{x} - e^{-x}}{e^{x} + e^{-x}}\).
Determine the symmetry of each function by checking \(f(-x)\): For \(\cosh x\), compute \(\cosh(-x)\) and compare it to \(\cosh x\) to see if it is even; for \(\sinh x\), compute \(\sinh(-x)\) and compare it to \(-\sinh x\) to check if it is odd; for \(\tanh x\), check if \(\tanh(-x) = -\tanh x\) to determine if it is odd.
Analyze the behavior and key points of each function: For \(\cosh x\), note it has a minimum at \(x=0\) with \(\cosh 0 = 1\); for \(\sinh x\), it passes through the origin with \(\sinh 0 = 0\); for \(\tanh x\), it passes through the origin and has horizontal asymptotes.
Identify asymptotes: \(\cosh x\) and \(\sinh x\) do not have asymptotes as they grow exponentially; \(\tanh x\) has horizontal asymptotes at \(y = 1\) and \(y = -1\) because as \(x \to \infty\), \(\tanh x \to 1\) and as \(x \to -\infty\), \(\tanh x \to -1\).
Sketch each graph using the above information: plot key points and symmetry, draw the shape of \(\cosh x\) (a 'U'-shaped curve), \(\sinh x\) (an 'S'-shaped curve through the origin), and \(\tanh x\) (an 'S'-shaped curve bounded by horizontal asymptotes at \(y=\pm 1\)).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m
도움이 되었나요?

주요 개념

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

Hyperbolic Functions

Hyperbolic functions include sinh x, cosh x, and tanh x, defined using exponential functions: sinh x = (e^x - e^{-x})/2, cosh x = (e^x + e^{-x})/2, and tanh x = sinh x / cosh x. They resemble trigonometric functions but relate to hyperbolas rather than circles.
추천 영상:
가이드 코스
5:50
Asymptotes of Hyperbolas

Even and Odd Functions

A function f(x) is even if f(-x) = f(x) for all x, meaning its graph is symmetric about the y-axis. It is odd if f(-x) = -f(x), showing symmetry about the origin. Determining this helps understand the symmetry properties of the given hyperbolic functions.
추천 영상:
가이드 코스
06:21
Properties of Functions

Asymptotes and Graph Behavior

Asymptotes are lines that a graph approaches but never touches. For tanh x, horizontal asymptotes occur at y = ±1 as x approaches ±∞. Understanding asymptotes helps in accurately sketching the behavior of hyperbolic functions at extreme values.
추천 영상:
가이드 코스
5:50
Asymptotes of Hyperbolas