Quantitative Aptitude Ques 1805
Question: Out of the given responses, one of the factors of $ x^{3}-3x^{2}+3x+7 $ is
Options:
A) $ x^{2}-4x+7 $
B) $ x^{2}+4x+7 $
C) $ x^{2}+4x-7 $
D) $ x^{2}-4x-7 $
Show Answer
Answer:
Correct Answer: A
Solution:
- Given expression, $ f(x)=x^{3}-3x^{2}+3x+7 $ By Hit and Trial, Put $ x=-1 $
$ \therefore $ $ f(-1)={{(-1)}^{3}}-3{{(-1)}^{2}}+3(-1)+7 $ $ =-1-3-3+7=0 $ So, $ x=-1 $ or $ (x+1) $ is the factor of the expression. Now, dividing expression by $ (x+1). $ Hence, $ (x^{2}-4x+7) $ is the factor of the expression $ x^{3}-3x^{2}+3x+7. $
BETA
