Answer: 203
Step-by-step explanation:
The given function : [tex]f(x) = 11x^2 + 5x[/tex]
Now, we differentiate the given function with respect to x on the both sides , we get
[tex]f'(x) = (2)11x + 5[/tex] [Since [tex](x^n)'=nx^{n-1}[/tex] ]
[tex]\Rightarrow\ f'(x)=22x+5[/tex]
Substitute x = 9 , we get
[tex]\Rightarrow\ f'(9)=22(9)+5\\\\\Rightarrow\ f'(9)=198+5\\\\\Rightarrow\ f'(9)=203[/tex]
Hence, the derivative of the given function at x= 9 is 203.