Question

@perl

Answer 1

one moment :)

Answer 2

okay(:

Answer 3

yay(:

Answer 4

A girls throws a tennis ball straight into the air with a velocity of 64 feet/sec. If acceleration due to gravity is -32 ft/sec^2, how many seconds after it leaves the girl's hand will it take the ball to reach its highest point? Assume the position at time t = 0 is 0 feet.

a(t) = -32

integrate acceleration to get velocity
v(t) = -32t + c1
v(0) = 64
v(t) = -32t + 64

integrate velocity to get position
h(t) = -32t^2 /2 + 64t + yo
h(0) = 0
h(t) = -16t^2 + 64t + 0

max height occurs when t = -b/(2a)
t = -64/(2*-16) = 2 seconds. so you are correct

Answer 5

Find the velocity, v(t), for an object moving along the x-axis if the acceleration, a(t), is 3t^2 + cos(t) and v(0) = 2

a(t) = 3t^2 + cos(t)

derivative of acceleration is velocity

v(t) = 3*2t + (-sin(t))
v(t) = 6t - sin t

Answer 6

im done! thank you so much(:

Answer 7

how many did you get correct?

Answer 8

can you post a screenshot

Answer 9

oh wait , only 2 wrong

Answer 10

that should be 3
http://www.wolframalpha.com/input/?i=integrate+%28-t^2%2B4%29%2C+t%3D+0..3

Answer 11

im redoing it though

Answer 12

its all good(: its not like its a test or anything, just practice(:

Answer 13

ok

Answer 14

why was this one wrong
http://assets.openstudy.com/updates/attachments/54b197fde4b0dbc68afeb207-wade123-1420926473420-screenshot20150110at4.44.37pm.png

Answer 15

i have no idea:/ dont even worry about it, ill ask my teacher because you were right

Answer 16

oh ok :)

Answer 17

find the average value, i could not read the given interval Θ

Answer 18

do you see it?

Answer 19

@perl

Answer 20

@perl helloo??

Answer 21

yes

Answer 22

i cant see the interval