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by **Rico.** on Mon Feb 25, 2013 3:53 am

I can't solve this problem: 3/ (x - 2). For what values of x is |f(x) -4| < or = to 0.005?
Thanks in advance for your help.

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by **nona.m.nona** on Mon Feb 25, 2013 4:12 am

Rico. wrote:I can't solve this problem: 3/ (x - 2).

What do you mean by "solving" this expression?

Rico. wrote:For what values of x is |f(x) -4| < or = to 0.005?

What is the formula for f(x)?

by **Rico.** on Mon Feb 25, 2013 4:17 am

The problem is to solve for what values of x is |f(x)-4| < or = to 0.05. f(x)= 3x/ (x-4)

by **nona.m.nona** on Mon Feb 25, 2013 12:25 pm

Rico. wrote:The problem is to solve for what values of x is |f(x)-4| < or = to 0.05. f(x)= 3x/ (x-4)

This topic should have been covered when you were studying pre-calculus algebra. The statement converts as follows:

. . . $|f(x)\, -\, 4|\, \leq\, 0.05$

. . . $-0.05\, \leq\, \frac{3x}{x\, -\, 4}\, -\, 4\, \leq\, 0.05$

. . . $3.95\, \leq\, \frac{3x}{x\, -\, 4}\, \leq\, 4.05$

Then solve the two cases: where x - 4 < 0 and where x - 4 > 0. You may find this article to be instructive.

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