208k views
2 votes
Let f(x)=x^3-6x+3 i. find the domain of the function and f’(x) in the domain.​

User Robz
by
3.6k points

2 Answers

5 votes

Explanation:


thank \: you

Let f(x)=x^3-6x+3 i. find the domain of the function and f’(x) in the domain.​-example-1
User Eric Liu
by
3.3k points
1 vote

Domain of a any cubic function
f(x)=ax^3+bx^2+cx+d is defined to be always
\mathbb{R}.

The derivative with respect to x of your cubic function is,


(d)/(dx)f(x)=f'(x)

to find the derivative of a polynomial function, simply take a derivative of each factor and sum them up,


(d)/(dx)x^3=3x^2 by the rule
(d)/(dx)x^m=mx^(m-1) where
m\in\mathbb{R}


(d)/(dx)-6x=-6


(d)/(dx)3=0

So the derivative is,


f'(x)=3x^2-6

both derivative and the original function have equal domain.

Hope this helps :)

User Unjuken
by
4.0k points