find the parent function of y = (-1/2)(x-1)^2 - 5

1 answer

The given function is

\[ y = \left(-\frac{1}{2}\right)(x-1)^2 - 5. \]

To identify the parent function, we can look at the structure of the function. The expression \((x-1)^2\) suggests that the basic shape of the function is a quadratic function, which is characterized by the general equation

\[ y = x^2. \]

This means that the parent function is:

Parent Function: \( y = x^2 \)

The transformations applied to the parent function to obtain the given function are:

  1. Horizontal Shift: The term \((x-1)\) indicates a shift to the right by 1 unit.
  2. Vertical Stretch/Compression: The coefficient \(-\frac{1}{2}\) indicates a vertical compression (since the absolute value is less than 1) and a reflection in the x-axis (due to the negative sign).
  3. Vertical Shift: The \(-5\) indicates a downward shift by 5 units.

Putting all these transformations together gives you the function described:

  1. Shift right by 1 unit
  2. Reflect across the x-axis
  3. Compress vertically by a factor of 2
  4. Shift down by 5 units

Thus, the parent function is \( y = x^2 \).