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Ch. 2 - Limits
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243당신이 사용하는 게 아니라요?교과서 변경
2장, 문제 2.31d

A projectile is fired vertically upward and has a position given by s(t)=−16t^2+128t+192, for 0≤t≤9.


d. For what values of t on the interval [0, 9] is the instantaneous velocity positive (the projectile moves upward)?

검증된 단계별 안내
1
insert step 1> Find the velocity function by differentiating the position function s(t) with respect to time t.
insert step 2> The position function is s(t) = -16t^2 + 128t + 192. Differentiate this to get the velocity function v(t).
insert step 3> The derivative of s(t) is v(t) = ds/dt = -32t + 128.
insert step 4> Set the velocity function v(t) > 0 to find when the projectile is moving upward.
insert step 5> Solve the inequality -32t + 128 > 0 to find the values of t for which the velocity is positive.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m
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주요 개념

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

Instantaneous Velocity

Instantaneous velocity is the rate of change of position with respect to time at a specific moment. It is calculated as the derivative of the position function, s(t). For the given function s(t) = -16t^2 + 128t + 192, finding the derivative s'(t) will provide the instantaneous velocity at any time t.
추천 영상:
06:29
Derivatives Applied To Velocity

Derivative

The derivative of a function measures how the function's output changes as its input changes. In calculus, it is a fundamental tool for analyzing rates of change. For the position function s(t), the derivative s'(t) will yield a new function that describes the velocity of the projectile at any time t, allowing us to determine when the projectile is moving upward.
추천 영상:
05:44
Derivatives

Critical Points and Intervals

Critical points occur where the derivative of a function is zero or undefined, indicating potential changes in the function's behavior. To find when the instantaneous velocity is positive, we need to analyze the sign of the derivative s'(t) over the interval [0, 9]. This involves identifying critical points and testing intervals to determine where the velocity is greater than zero.
추천 영상:
04:50
Critical Points