Answer:
If you actually meant f(x)=2x+3x−1 ,
then note it can be rewritten as:
f(x)=2x−2+5x−1=2+5x−1=y
At this point you can find x in terms of y (“make x the subject”):
y−2=5x−1⟹1y−2=x−15
⟹x=5y−2+1=y+3y−2
Switch variables back to x, and you have the inverse function of f:
g(x)=x+3x−2
How do you know you’ve calculated correctly? The composition of f with g should result in x — that is, evaluate f(g) and you should get the result x:
Step-by-step explanation:
14,000+2.1%(0.021)x
x is how many years
-2n+4n=14
2n=14
n=7
Check answer
7-3(7)= 14-4(7)
7-21= 14-28
-14=-14
n= 7