Question

Part 3
please help
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Answer 1

I'm taking "part 3" to mean the 3rd of the posted questions.

If
`f(x)=(x^3+2x)\ln x`, then

`f'(x)=(x^3+2x)'\ln x+(x^3+2x)(\ln x)'=(3x^2+2)\ln x+\frac{x^3+2x}x`

`\implies f'(x)=(3x^2+2)\ln x+x^2+2`

Then when
`x=1`, we get
`f'(1)=3`.