Maths Brain workout for anyone who wants a go :)

[Daws]

The quantity T is defined by the formula

T = (3a^2 b^3/2) / c^4
(That's 3 a squared times b to the power 3 over 2 all divided by c to the power 4 just in case it is unclear)

If the relative errors in a, b and c are -0.015, 0.02 and 0.0025, respectively, find
i) the relative error in T;
ii) the maximum relative error in T.



I'm not understanding it too well atm, anyone wanna explain ?

 

[Daws]

T = (3a^2 b^3/2) / c^4
(That's 3 a squared times b to the power 3 over 2 all divided by c to the power 4 just in case it is unclear)

Blah. I found code to make it good on other forums... but no doesn't work on these ones... damn supertext ;z Anyone know if there is a code for supertext that works here?

 

[Lumikki]

Righto.

 

[sibanac]

The quantity T is defined by the formula

T = (3a^2 b^3/2) / c^4
(That's 3 a squared times b to the power 3 over 2 all divided by c to the power 4 just in case it is unclear)

If the relative errors in a, b and c are -0.015, 0.02 and 0.0025, respectively, find
i) the relative error in T;
ii) the maximum relative error in T.



I'm not understanding it too well atm, anyone wanna explain ?

not sure what to do with the relative rell error
ii) would be
T = (3(a+a*-0.015)^2 (b+b*0.02)^3/2) / (c+c*0.0025)^4

still trying to work out i)

hope it helps abit

 

[sibanac]

as for i)

if we say that my prev post was the calculation of T(max).

then T(rel) should be
(T(max)-T)/T=T(rel)



*disclaimer, If you flunk an exam because i was wrong it isnt my fault, you should have paided better attention durring class

 

[Coren]

I think you might have to take partial derivatives of T w.r.t. a, b and c...which then gives you relations for how much T is affected by changes in each of the others. This is all kinda hazy but I'm pretty sure I had a similar question last year (I couldn't do it then, I allegedly can now but....meh...also cba to find my notes).

Good luck

 

[Maddius]

10

 

[Daws]

*disclaimer, If you flunk an exam because i was wrong it isnt my fault, you should have paided better attention durring class

Heh, cheers ;-) I was just posting to see if anyone could explain it, seems you did a pretty good job, I am going to check with my friends now

 

[Chilly]

hmmmmmmmm..........too much beer and sleeping through lectures means a 2nd year physics student cant look at that wihtout crying, granted Im drunk now but stfu!

 

[Hercules-DF]

Fish!

 

[Ilienwyn]

bleh, once I knew some relatively nice maths. Now, I look that and I got no clue what's going on!

 

[Tallen]

Do your own bloody homework