Question

Help! Medal and Fan, if you can help!

solve: f(t)=20+150*ln(8t+1) and I have to find 10 minutes, which will then give me the equation f(10)=20+150*ln(8(10)+1)

Can someone help solve it?

Answer 1

@YanaSidlinskiy This is the one!

Answer 2

Aww...What a problem..

Answer 3

Yeah!
I got f(10)=170*ln(81) but then i'm stuck and i don't even know if it's right..

Answer 4

or at least it should be 20+150*ln(81)... but still stuck on what i should do

Answer 5

ln= ? ? What do you mean?

Answer 6

f(10)=170*ln(81)

Answer 7

That's how far I got, but i need to get the temp.

Answer 8

@phi Can you help?

Answer 9

@AccessDenied, can you help with this?

Answer 10

Or someone -.- @mathmale ?

Answer 11

@whpalmer4 ?

Answer 12

\[ f(t)=20+150*\ln(8t+1)\]
\[f(10) = 20+150*\ln(8(10)+1)\]\[f(10) = 20+150*\ln(81)\]

Answer 13

@whpalmer4 yes, i got to that part but can't i solve to get one number? I need to find the temp (f(t))

Answer 14

So don't you have a calculator?

Answer 15

No, actually...

Answer 16

Or select values of \(\ln x\) committed to memory? :-)

\[\ln 3 \approx 1.09861\]so \[\ln 81 = \ln 3^4 = 4\ln 3 \approx 4*1.09861 \approx 4.394\]

Answer 17

http://wolframalpha.com is a fine calculator, as is http://web2.0calc.com/

Answer 18

I've tried wolframalpha, that isn't working... But i'll try the other one. Thanks

Answer 19

oh sure it is.... http://www.wolframalpha.com/input/?i=ln+81

Answer 20

Ah... Okay. Thanks for answering! :)

Answer 21

actually, it's the other one that isn't working now :-)

Answer 22

if you just go to google.com and type your expressions into the search box, that usually works, too. https://www.google.com/#q=ln+81

Answer 23

I haven't tried the other one yet... I put it in wrong in wolfram, that's why i couldn't get any answer.

Answer 24

wolfram would probably interpret your problem almost directly:
http://www.wolframalpha.com/input/?i=f(t)%3D20%2B150*ln(8t%2B1)+with+t%3D10

Answer 25

This is awesome help! I'm looking through it now :D Thanks !!

Answer 26

it's a great tool, but resist the temptation to have it do your homework!

Answer 27

Lol, yup. Got you.. That's why I come here to get help so i can work with and understand it

Answer 28

Find the interquartile range of the data.



A.
6

B.
8

C.
9

D.
20

Answer 29

@natedog12 do not post your questions in someone else's question!

Answer 30

dude that was 30 minutes ago

Answer 31

Doesn't matter, just don't do it.