Find the positive area of the function
y=(x+5)2−4
To find the positive area of the function y=(x+5)2−4, follow these steps:
- Step 1: Identify when the function is greater than zero.
We need (x+5)2−4>0.
- Step 2: Find the roots of (x+5)2−4=0.
Solving, we set: (x+5)2=4.
- Step 3: Solve for (x+5)2=4.
Take the square root on both sides: x+5=±2.
This gives: x+5=2 or x+5=−2.
Thus, x=−3 or x=−7.
- Step 4: Identify intervals.
We need to look at intervals determined by the roots: (−∞,−7), (−7,−3), and (−3,∞).
- Step 5: Determine where the function is positive by testing each interval:
- For x<−7, choose x=−8, then ((−8)+5)2−4=9−4=5 (positive).
- For −7<x<−3, choose x=−5, then ((−5)+5)2−4=0−4=−4 (negative).
- For x>−3, choose x=0, then (5)2−4=25−4=21 (positive).
Therefore, the positive area of the function is for x<−7 and −3<x.