What’s the inverse? can someone also show the steps?

      -1

    f    (x)  =  (1/2)((x^2 - 5)

Step-by-step explanation:

First:  replace that "f(x)" with "y:"  y = √(2x + 5)

Second, interchange x and y:  x = √(2y + 5)

Third, solve this result for y.  Begin by squaring both sides:

 x^2 = 2y + 5

 Next, subtract 5 from both sides:  x^2 - 5 = 2y

 Lastly, divide both sides by 2:  y = (1/2)(x^2 - 5)

 Fourth:  replace y with

      -1

    f    (x):

      -1

    f    (x)  =  (1/2)((x^2 - 5)