Question

A roast is removed from the freezer at a refrigerator and left on the counter to defrost. The temperature of the roast was -4 degrees centigrade when it was removed from the freezer and t hours later, was inc. at a rate of
T'(t) = 7e^.35t.
find a formula for the temp of the roast after hours
answer is 16-20e^-.35t
i dont get where the 16 coming from

Answer 1

what i have so far
\[\int\limits7e^-.35t dt\]
\[\int\limits7+ \int\limits e^-.35t\]
7[1/.35e^-.35]
my answer
-20e^-.35+c

Answer 2

ok uhm let's start by correcting your integration\[\int 7e^{-.35t}dt=7\int e^{-.35t}dt\]

Answer 3

try again for me please =)

Answer 4

oops i didnt see u had a mission :P

Answer 5

haha it's cool

Answer 6

are u there @elskydiablo

Answer 7

yes

Answer 8

can you please answer me then, please redo the problem showing your steps

Answer 9

\[7\int\limits e ^{-.35t } dt\]
7[-1/.35e^-.35]
7/-.35[e^-.35]
-20.e^-.35?

Answer 10

ur messing up the integration for e

Answer 11

how?

Answer 12

You are writing it incorrectly but achieving a correct answer

Answer 13

can you please write your first step in LaTex

Answer 14

LaTex?

Answer 15

The equation option at the bottom of the dialogue box. It is actually a math script named latex.

Answer 16

here copy this to start \[7\int\limits e ^{-.35t } dt\]

Answer 17

oops [[7\int\limits e ^{-.35t } dt]]

Answer 18

dan change the first and second to last bracket to a \

Answer 19

ok i see

Answer 20

\[7\int\limits e ^{-.35t} dt\]
\[7\int\limits e ^{-.35t}\dt]
\[7\int\limits 1/-.35e ^{-.35t}\dt]
\[7/-.35 e ^{-.35t}\]
is this right so far?

Answer 21

\[7\int\limits e ^{-.35t } dt\]
\[=(7/-0.35)e ^{-.35t } + c \]
\[=-20e ^{-.35t } + c\]

Answer 22

ya u got it right now, u kept forgetting the t

Answer 23

now apply that inital condition to it

Answer 24

T(0)=-4

Answer 25

yes i see what i did wrong.

Answer 26

yea that's right now you need to find your c, right? and you know that T(0)=-4

Answer 27

So what is your next step?

Answer 28

in words, you don't have to type it

Answer 29

t(0)=-20e^-.35(0)+c=-4

Answer 30

right next what should you do?

Answer 31

-20+c=-4
c=16

Answer 32

yep!
congrats you did it!

Answer 33

thank you so much

Answer 34

np

Answer 35

listen to my elsky! u need to become MORE SERIOUS ABOUT THESE THINGS!

Answer 36

i expect you to be doing boundary value laplace PDE EQUATIONS by the time i see u again

Answer 37

good bye