Functions Question 416
Question: The domain of the real valued function $ f(x)=\sqrt{5-4x-x^{2}}+x^{2}\log (x+4) $ is
Options:
A) $ (-5,1) $
B) $ -5\le xandx\ge 1 $
C) $ ( -4,1 ] $
D) $ \phi $
Show Answer
Answer:
Correct Answer: C
Solution:
[c] $ f(x)=\sqrt{5-4x-x^{2}}+x^{2}\log (x+4) $
$ \Rightarrow 5-4x-x^{2}\ge 0,x+4>0 $
$ \Rightarrow (x+5)(x-1)\le 0,x>-4 $
$ \Rightarrow -5\le x\le 1,x>-4\Rightarrow -4<x\le 1. $
BETA
