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Ch. 1 - Functions
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243당신이 사용하는 게 아니라요?교과서 변경
1장, 문제 65e

{Use of Tech} Height and time The height in feet of a baseball hit straight up from the ground with an initial velocity of 64 ft/s is given by h= ƒ(t) = 64t - 16t²  where t is measured in seconds after the hit.


e. At what time is the ball at a height of 10 ft on the way down? 

검증된 단계별 안내
1
Step 1: Set up the equation for the height of the ball. We are given that the height function is \( h(t) = 64t - 16t^2 \). We need to find the time \( t \) when the height \( h(t) = 10 \) feet.
Step 2: Substitute 10 for \( h(t) \) in the equation: \( 10 = 64t - 16t^2 \).
Step 3: Rearrange the equation to form a standard quadratic equation: \( 16t^2 - 64t + 10 = 0 \).
Step 4: Use the quadratic formula \( t = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \) to solve for \( t \), where \( a = 16 \), \( b = -64 \), and \( c = 10 \).
Step 5: Calculate the discriminant \( b^2 - 4ac \) and then find the two possible values for \( t \). Choose the value of \( t \) that corresponds to the ball being on its way down.

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.

Quadratic Functions

The height function h(t) = 64t - 16t² is a quadratic function, which is a polynomial of degree two. Quadratic functions graph as parabolas and can model various physical phenomena, such as projectile motion. Understanding the properties of parabolas, including their vertex and intercepts, is essential for analyzing the height of the baseball over time.
추천 영상:
6:04
Introduction to Polynomial Functions

Solving Quadratic Equations

To find the time when the baseball reaches a height of 10 ft, we need to solve the equation 64t - 16t² = 10. This involves rearranging the equation into standard form and applying methods such as factoring, completing the square, or using the quadratic formula. Mastery of these techniques is crucial for determining specific values of t in quadratic scenarios.
추천 영상:
5:02
Solving Logarithmic Equations

Projectile Motion

The scenario describes projectile motion, where an object is thrown vertically and affected by gravity. The height of the object over time can be modeled using a quadratic equation, where the initial velocity and gravitational acceleration influence the trajectory. Understanding the principles of projectile motion helps in interpreting the behavior of the baseball as it rises and falls.
추천 영상:
가이드 코스
06:51
Derivatives Applied To Acceleration Example 2