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xddxogm3
11-19-2004, 12:36 AM
I was just wondering if someone can check my work on this problem.


(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

Zach L.
11-19-2004, 12:42 AM
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).

Thantos
11-19-2004, 12:43 AM
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.

xddxogm3
11-19-2004, 12:43 AM
thanks for the confirmation.
slowly but surely i'm learning more skills for the code.
;0)