# And more Mathematics (logarithms)

This is a discussion on And more Mathematics (logarithms) within the A Brief History of Cprogramming.com forums, part of the Community Boards category; I was just wondering if someone can check my work on this problem. Code: (1/4)^x=75 //original equation x log (1/4) ...

1. ## And more Mathematics (logarithms)

I was just wondering if someone can check my work on this problem.
Code:
```
(1/4)^x=75		//original equation
x log (1/4) = log 75	//take log of each side
x= log 75 / log (1/4)   //divide by log (1/4)
x = -3.1144		//solve```
I attempted to put the resulting x value back into the following equation as a check
-75+(1/4)^x=0
and got the following answer on my check 2.14e-10

2. Yep, the work is right. And the value you got back checking is easily accounted for by rounding/truncating errors (10^-10 is negligible compared to the other quantities involved).

3. You work is correct. The different of 2.14e-10 is small enough to account for the rounding you did when you took x out of its exact form.

4. thanks for the confirmation.
slowly but surely i'm learning more skills for the code.
;0)