Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
lexusbreon
Group Title
If a stone is thrown down at 100 ft/s from a height of 1,250 feet, its height after t seconds is given by s = 1,250 − 100t − 16t^2
Estimate its instantaneous velocity at time t = 2
 one year ago
 one year ago
lexusbreon Group Title
If a stone is thrown down at 100 ft/s from a height of 1,250 feet, its height after t seconds is given by s = 1,250 − 100t − 16t^2 Estimate its instantaneous velocity at time t = 2
 one year ago
 one year ago

This Question is Closed

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
We know that the equation for instantaneous velocity is \( f'(x)=\large \frac{f(x+h)f(x)}{(x+h)x}\)
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
Are you familiar with this equation?
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
so \(f(t)=1250100t16t^2\) \(f(t+h)=1250100(t+h)16(t+h)^2\) so \(f'(x)= \large \frac{(1250100(t+h)16(t+h)^2)(1250100t16t^2)}{(x+h)x}\) \(f'(x)=\large \frac{1250100t100h16t^232th16h^21250+100t+16t^2}{h}\) \( f'(x)=\large \frac{100h32th16h^2}{h}\) \(f'(x)= \large \frac{h(10032t16h)}{h}\) \(f'(x)=(10032t16h)\)
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
Ok Are you familiar with limits? Like what does f'(t) equal as h approaches 0?
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
Did ya follow so far?
 one year ago

lexusbreon Group TitleBest ResponseYou've already chosen the best response.0
Yes I follow so far
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
Ok and keep in mind by accident I used X's in stead of T's so just ignore that
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
dw:1373424544924:dw
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
ok so the difference btwn x and x+h is just h
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
Basically we have 2 points; x and x+h and we want them to beee sooooo close together So we want h to be realllllly small So we want h to be like nearly 0 Like the number right next to 0 So there is this method called limits and we limit the equation meaning we want to see what the equation will equal as h APPROACHES 0 \(\large f'(t)_{\lim h \to 0} 10032t16h\) Now there is only one term that has h in it which is 16h Now as h approaches 0 then 16h approaches 0 since 16*.00000000001=.00000000016 So its basically 0 so we consider it as if it is 0 and just trash that whole term \(\large f'(t)_{\lim h \to 0} 10032t16h=10032t\) Now we need to find the Instantaneous velocity when t=2 So we plug into our equation t=2 \(f'(2)=10032(2)=164
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
So at t=2 the stone is travelling 164 ft/s downwards
 one year ago

swissgirl Group TitleBest ResponseYou've already chosen the best response.1
I hope you followed :)
 one year ago

lexusbreon Group TitleBest ResponseYou've already chosen the best response.0
Thank You so much!!
 one year ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.