Find the standard representation of the following function
f(x)=(−x−2)2−5
To find the standard representation of the quadratic function f(x)=(−x−2)2−5, we'll proceed with the following steps:
- Step 1: Expand the quadratic expression (−x−2)2.
- Step 2: Simplify the expression resulting from the expansion.
- Step 3: Subtract the constant term −5.
Let's execute these steps in detail:
Step 1: Expand the expression (−x−2)2.
To expand, use the formula (a+b)2=a2+2ab+b2, where a=−x and b=−2.
(−x−2)2=(−x)2+2(−x)(−2)+(−2)2.
Step 2: Calculate the expanded form.
(−x)2=x2,
2(−x)(−2)=4x,
and (−2)2=4.
Combining these, we have:
x2+4x+4.
Step 3: Incorporate the constant from the original function.
The original function is f(x)=(−x−2)2−5. Thus, we subtract 5 from the expanded result:
f(x)=x2+4x+4−5, which simplifies to:
f(x)=x2+4x−1.
Therefore, the standard form of the given quadratic function is f(x)=x2+4x−1.
f(x)=x2+4x−1