find the inverse of cube of 2x-5

1 answer

To find the inverse of the function \( f(x) = (2x - 5)^3 \), we follow these steps:

  1. Replace \( f(x) \) with \( y \): \[ y = (2x - 5)^3 \]

  2. Switch \( x \) and \( y \) to find the inverse: \[ x = (2y - 5)^3 \]

  3. Solve for \( y \):

    • Take the cube root of both sides: \[ \sqrt[3]{x} = 2y - 5 \]

    • Add 5 to both sides: \[ \sqrt[3]{x} + 5 = 2y \]

    • Divide by 2: \[ y = \frac{\sqrt[3]{x} + 5}{2} \]

  4. Write the inverse function: \[ f^{-1}(x) = \frac{\sqrt[3]{x} + 5}{2} \]

So, the inverse of the cube of \( 2x - 5 \) is: \[ f^{-1}(x) = \frac{\sqrt[3]{x} + 5}{2} \]