Functions Question 613
Question: If $ f(x)=4x^{3}+3x^{2}+3x+4 $ , then $ x^{3}f( \frac{1}{x} ) $ is
[SCRA 1996]
Options:
A) $ f(-x) $
B) $ \frac{1}{f(x)} $
C) $ {{( f( \frac{1}{x} ) )}^{2}} $
D) $ f(x) $
Show Answer
Answer:
Correct Answer: D
Solution:
$ x^{3}f( \frac{1}{x} )=x^{3},[ \frac{4}{x^{3}}+\frac{3}{x^{2}}+\frac{3}{x}+4 ] $ $ =4+3x+3x^{2}+4x^{3}=f(x) $ .
BETA
