To study the interactive effects of the different variables on the production of glycerin laurate, response surface methodology comprising a full fractional 5-level and 3-factors design was used in this study, and a total of 15 experiments were designed.
Please refer the book "Design and Analysis of Experiments" by R.Panneerselvam and you can get the solution if you go through the tutorials of Design Expert Software
Thanks for your responses
How can I get this equation from design expert software in terms of B0+Bixi+Biixi2+.....
Before worrying about how to write the equation make sure your process may be described by a second-degree equation. Not any process is eligible.
Once your model was successfully developed, then click analysis and after that go to ANOVA page in Design Expert Software and scroll down then you can get equation in terms of B0+Bixi+Biixi2+.....
For this you can see some tutorial video.
Estimating the degree of the polynomial is the most important and largely unsolved problem in most cases.
once you run Design expert go into analysis and select the response that you want to analyze and go to ANOVA and then click on coefficient or coded equation or actual equation and then you can convert it into the general polynomial equation by identifying the linear terms, quadratic terms and interaction terms in such a way; y= βo + βiXi+βjXj +---βijXiXj + ---βiiXi2 + βjjXjj2 + ----