Find the inverse of f(x)=2x^3-1

Question

campbell_st · Answer

start by swapping x and y

so it becomes 

$$x = 2y^3 - 1$$

noe make y the subject... that will be the inverse

anonymous · Answer

In order to find the inverse of a function, first, replace f(x) with y. Next, change your y into an x, and your x into a y. Now solve for y.

Example:
$$f(x) = 3x-4$$$$y=3x-4$$$$x=3y-4$$$$x+4=3y$$$$\frac{x+4}{3}=y$$$$f^{-1}(x)=\frac{x+4}{3}$$

anonymous · Answer

I already know those steps. I'm just confused in how to work out diving 2y^3 since it's cubed

campbell_st · Answer

ok... start by adding 1 to both sides

$$x + 1 = 2y^3$$ 

now divide by 2

$$\frac{x + 1}{2} = y^3$$

lastly take the cube root of both sides

hope it helps