1. Sulfuric acid densities empirical table: column I concentrations in 0.5% increments, column II the corresponding measured densities.
2. I plot the curve "measured density"=f(%).
3. I plot the trendline as 5th order polynomial with R=1, perfect visual match.
4. Using this polynomial equation I calculate (in column 3) the new densities. This data is different from the measured densities.
5. I plot equation "calculated density"=f(%) on the same graph; the curve should match the first one, but it does not.
6. I plot the trendline for this second curve as 5th order polynomial; it is identical to the first equation.
The curves are clearly different, but the equations identical!! What am I missing here?
2. I plot the curve "measured density"=f(%).
3. I plot the trendline as 5th order polynomial with R=1, perfect visual match.
4. Using this polynomial equation I calculate (in column 3) the new densities. This data is different from the measured densities.
5. I plot equation "calculated density"=f(%) on the same graph; the curve should match the first one, but it does not.
6. I plot the trendline for this second curve as 5th order polynomial; it is identical to the first equation.
The curves are clearly different, but the equations identical!! What am I missing here?