Step 1 :Given the integral \(\int_{0}^{1} x(9 \sqrt[3]{x}+8 \sqrt[4]{x}) d x\)
Step 2 :Distribute the x inside the parentheses to get \(\int_{0}^{1} (9x^{4/3}+8x^{5/4}) d x\)
Step 3 :Separate the integral into two parts: \(\int_{0}^{1} 9x^{4/3} dx + \int_{0}^{1} 8x^{5/4} dx\)
Step 4 :Calculate the integral of each part separately
Step 5 :The integral of \(9x^{4/3}\) from 0 to 1 is \(\frac{27}{7}\)
Step 6 :The integral of \(8x^{5/4}\) from 0 to 1 is \(\frac{32}{9}\)
Step 7 :Add the results of the two integrals to get the final answer
Step 8 :\(\frac{27}{7} + \frac{32}{9} = 7.41269841269841\)
Step 9 :Final Answer: \(\boxed{7.41269841269841}\)