# Homework Help: I want check my answer ()()()

1. Nov 12, 2009

### r-soy

Hi

I want check my answer two Question

Question 1

Question 2

2. Nov 12, 2009

### Staff: Mentor

You're starting with an equation, so each step should be a new equation.
xlog x = 100x
log(xlog x) = log(100x)
(log x)(log x) = log 100 + log x
Continue from there. You should end up with a value of x that is correct to three significant digits.

3. Nov 12, 2009

### r-soy

Hi mark

why we said log 100 + log x ?

why + log x ?????

4. Nov 12, 2009

Because

$$\log(ab) = \log(a) + \log(b)$$

5. Nov 14, 2009

### r-soy

thanks >>

6. Nov 14, 2009

### Staff: Mentor

For Q2, your answer is close, but should be rounded to 34.7 years, to the nearest tenth of a year.

Also, there is no In operation. This is Ln, and stands for natural Logarithm, which in Latin is logarithmus naturalis.

BTW, you might get quicker help if you posted the problem and your work rather than posting a scanned copy of your work. Speaking for myself, it's much easier when I can write my response while looking at the work, rather than having to have two windows open and jump back and forth between them.