Question
Mathematics Question on Relations and functions
The domain of the function f(x)=x2+3x+2log2(x+3) is
A
R−−1,−2
B
R−−1,−2,0
C
(−3,−1) ∪ (−1,∞)
D
(−3,∞)−−1,−2
Answer
(−3,∞)−−1,−2
Explanation
Solution
Given function is f(x)=x2+3x+2log2(x+3)
Here, for existence of log
x+3>0
⇒x>−3
⇒x∈(−3,∞)
and for existence of f(x),
x2+3x+2=0
⇒(x+1)(x+2)=0
⇒x=−1,−2
Hence, required domain of f(x) is
(−3,∞)−−1,−2