Functions Question 527
Question: If $ f(x)=ax+b $ and $ g(x)=cx+d, $ then f$f{x}$=$g{f(x)} $ is equivalent to?
Options:
A) $ f(a)=g(c) $
B) $ f(b)=g(b) $
C) $ f(d)=g(b) $
D) $ f(c)=g(a) $
Show Answer
Answer:
Correct Answer: C
Solution:
[c] Given, $ f(x)=ax+b,g(x)=cx+d $ and $ f{g(x)}=g{f(x)} $
$ \Rightarrow f(cx+d)=g(ax+b)\Rightarrow a(cx+d)+b=c(ax+b)+d $
$ \Rightarrow acx+ad+b=cax+bc+d\Rightarrow ad+b=bc+d $
$ \Rightarrow f(d)=g(b) $
BETA
