Find the domain X where the inequality exists
2\log_3x<\log_3(x^2+2x-12)
Let's solve the inequality 2log3x<log3(x2+2x−12).
- Step 1: Apply the Power Property of Logarithms
The expression 2log3x can be rewritten as log3(x2) using the power property, which states alogb(x)=logb(xa).
Thus, the inequality transforms to:
log3(x2)<log3(x2+2x−12)
- Step 2: Remove the Logarithm by Ensuring Both Sides are Positive
Since log3(M)<log3(N) implies M<N when M>0 and N>0, the inequality becomes:
x2<x2+2x−12
Simplifying:
0<2x−12
Add 12 to both sides:
12<2x
Divide both sides by 2:
6<x
- Step 3: Consider the Domain Restrictions of the Logarithmic Terms
For both sides of the logarithmic inequality to be defined, we need to ensure:
- x>0
- Expression inside the right logarithm is positive: x2+2x−12>0
Solving x2+2x−12>0 involves factorization:
(x+4)(x−3)>0
This quadratic inequality gives critical points at x=−4 and x=3. Testing intervals around these points, the inequality holds when x<−4 or x>3. Considering the logarithmic condition x>0, we narrow it to x>3.
- Step 4: Combine All Results
The combined condition from steps 2 and 3 yield:
6<x
Therefore, the solution to the inequality is 6<x.