Step-by-step explanation:
The given function is :

(a) To find f(9), put x = 9 in the above expression.

(b) To find f(x+7), put x = x+7 in the above expression.

(c) To find f(-x), put x = -x in the above expression.

Hence, this is the required solution.
250m/s = x m/min
250m/s = x min/ 60s
250•60 = 1500
The airplane will travel 1500m per minute
Answer:
They are not commutative, because f(g(x)) and g(f(x) are not equal.
Step-by-step explanation:
In order for the composition of the functions to be commutative, we must have ...
f(g(x)) ≡ g(f(x))
for all values of x.
Here, we have f(g(x)) = 1 and g(f(x)) = 2. f(g(x)) and g(f(x)) are not equal, so the composition of the functions is not commutative.