Quadratic Completion 30De84
1. The problem asks to express the quadratic expression $x^2 + 6x + 5$ in the form $(x + a)^2 + b$, where $a$ and $b$ are constants.
2. We use the method of completing the square. The general formula is:
$$x^2 + 2ax + a^2 = (x + a)^2$$
3. Compare $x^2 + 6x + 5$ with $x^2 + 2ax + a^2$. Here, $2a = 6$ so $a = 3$.
4. Rewrite the expression:
$$x^2 + 6x + 5 = (x + 3)^2 - 3^2 + 5 = (x + 3)^2 - 9 + 5 = (x + 3)^2 - 4$$
5. Therefore, the expression in the form $(x + a)^2 + b$ is:
$$(x + 3)^2 - 4$$
6. The transformation from $y = x^2$ to $y = x^2 + 6x + 5$ can be described by rewriting the latter as:
$$y = (x + 3)^2 - 4$$
7. This means the graph of $y = x^2$ is shifted 3 units to the left (because of $x + 3$) and 4 units down (because of $-4$).
8. In terms of function notation, if $f(x) = x^2$, then the transformed function is:
$$y = f(x + 3) - 4$$
Final answer:
$$(x + 3)^2 - 4$$