Hi, I'm having trouble with this question.

Find the minimum for y

y=(a+x)(b+x)\cx

c,x,b,a>0

Can anyone help? Thanks.

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- September 5th 2009, 08:48 PMBobalinaAlgebra help
Hi, I'm having trouble with this question.

Find the minimum for y

y=(a+x)(b+x)\cx

c,x,b,a>0

Can anyone help? Thanks. - September 5th 2009, 09:02 PMsammylemon
Hi

To solve this problem lets first expand through

solve for dervitive

set y prime =0

solve for x

put x into y equations

and proove one of smaller thne the other - September 5th 2009, 09:04 PMBobalina
Sorry, what is 'lim'? Limit?

- September 5th 2009, 09:04 PMsammylemon
yes

- September 5th 2009, 09:07 PMBobalina
Thanks so far, although I still don't understand this part:

now you said a,b,c,x >0 so if we take a lim x-> 0

limx->0 ab/cx + b/c +a/c + x/c - September 5th 2009, 09:13 PMsammylemon
oh nvm im very wroung

hehe sorry

take the derivtive solve for x at y prime=0

you should get 2 values

find the lower value by pulling both into original y equations lower one is ur result

in this cause ull have to prove on os smaller then the other - September 5th 2009, 09:25 PMBobalina
Sorry, I don't really understand? :S