1)lim (4x-8)^5/2

x->6

2)The sales of a new product over a period of time are expected to follow the relationship

S(x)=14000 x² /7 x² +2000

where x is the amount of money spent on advertising

What is lim S(x)=

x-> ∞

Thank you.

Printable View

- Nov 7th 2008, 09:07 AMbeachbunny619Find the Limit
1)lim (4x-8)^5/2

x->6

2)The sales of a new product over a period of time are expected to follow the relationship

S(x)=14000 x² /7 x² +2000

where x is the amount of money spent on advertising

What is lim S(x)=

x-> ∞

Thank you. - Nov 7th 2008, 09:21 AMjames_bond
For the second one: $\displaystyle S(x)=\frac {14000\cdot x^2}{7000\cdot x^2+2000}=\frac {14000}{7000+\frac {2000}{x^2}}\longrightarrow \lim_{x\rightarrow\infty}=\frac {14000}{7000+0}=2$

- Nov 7th 2008, 02:14 PMbeachbunny619
That's not right.

- Nov 7th 2008, 02:22 PMPlato
There is a simple typo in that answer.

$\displaystyle S(x)=\frac {14000\cdot x^2}{7\cdot x^2+2000}=\frac {14000}{7+\frac {2000}{x^2}}\longrightarrow \lim_{x\rightarrow\infty}=\frac {14000}{7+0}=2000$