# Logarithmic Functions

• Jul 18th 2008, 02:14 PM
Dave53
Logarithmic Functions
In anesthesiology it is necessary to accurately estimate the body surface area of a patient. One formula for estimating body surface ares (BSA) in square metes of a patient of height H (in centimeters) and weight W (in grams ) is :

BSA=0.0003207H0.3W(0.7285-0.0188logW)

(The 0.3 is an exponent of H; the (0.7285-0.0188logW) is an exponent of W)

Find the BSA if W = 49895.2 grams and H = 162.56 centimeters.
• Jul 18th 2008, 03:44 PM
Soroban
Hello, Dave!

This seems to be just calculator-cranking.

Quote:

In anesthesiology it is necessary to accurately estimate the body surface area of a patient.
One formula for estimating body surface area (BSA) in square meters
of a patient of height H (in centimeters) and weight W (in grams ) is:

. . $\displaystyle \text{BSA}\;=\;0.0003207\,H^{0.3}\,W^{(0.7285-0.0188\log W)}$

Find the BSA if: W = 49895.2 grams and H = 162.56 cm.

We have: .$\displaystyle \text{BSA} \;=\;(0.0003207)(162.56)^{0.03}(49895.2)^{(0.7285 - 0.0188\log 49895.2)}$

. . Go for it!

• Jul 18th 2008, 03:50 PM
Dave53
This is an online course I'm taking and the lesson plan does not explain in clear enough terms for me. My math skills are not my best skills and are 31 years old (The last time I took a math class-1976).