3.3 differentiation rules - ds\n(6 points)\nlet ( f ( x ) = \frac { 3 x ^ { 2 } + 3 x + 7 } { sqrt { x } }…

3.3 differentiation rules - ds\n(6 points)\nlet ( f ( x ) = \frac { 3 x ^ { 2 } + 3 x + 7 } { sqrt { x } } ). find the following:\n( f ^ { prime } ( x ) = )\n( f ^ { prime } ( 9 ) = )\nnote: you can earn partial credit on this problem.\nnote: you are in the reduced scoring period. all work counts for 85%\npreview my answers submit answers\nyou have attempted this problem 0 times.\nyou have 5 attempts remaining.
Answer
Explanation:
Step1: Simplify the function
Rewrite ( f(x)=\frac{3x^{2}+3x + 7}{\sqrt{x}}=3x^{2-\frac{1}{2}}+3x^{1-\frac{1}{2}}+7x^{-\frac{1}{2}}=3x^{\frac{3}{2}}+3x^{\frac{1}{2}}+7x^{-\frac{1}{2}})
Step2: Apply the power rule ( (x^{n})^\prime=nx^{n - 1})
( f^\prime(x)=3\times\frac{3}{2}x^{\frac{3}{2}-1}+3\times\frac{1}{2}x^{\frac{1}{2}-1}+7\times(-\frac{1}{2})x^{-\frac{1}{2}-1}) ( f^\prime(x)=\frac{9}{2}x^{\frac{1}{2}}+\frac{3}{2}x^{-\frac{1}{2}}-\frac{7}{2}x^{-\frac{3}{2}})
Step3: Calculate ( f^\prime(9))
Substitute ( x = 9) into ( f^\prime(x)): ( f^\prime(9)=\frac{9}{2}\sqrt{9}+\frac{3}{2}\frac{1}{\sqrt{9}}-\frac{7}{2}\frac{1}{(\sqrt{9})^{3}}) ( f^\prime(9)=\frac{9}{2}\times3+\frac{3}{2}\times\frac{1}{3}-\frac{7}{2}\times\frac{1}{27}) ( f^\prime(9)=\frac{27}{2}+\frac{1}{2}-\frac{7}{54}) ( f^\prime(9)=\frac{27 + 1}{2}-\frac{7}{54}=\frac{28}{2}-\frac{7}{54}=14-\frac{7}{54}=\frac{14\times54-7}{54}=\frac{756 - 7}{54}=\frac{749}{54})
Answer:
( f^\prime(x)=\frac{9}{2}x^{\frac{1}{2}}+\frac{3}{2}x^{-\frac{1}{2}}-\frac{7}{2}x^{-\frac{3}{2}}), ( f^\prime(9)=\frac{749}{54})