Answer:
To evaluate the composite functions (f◦g), (g◦f), (f◦f), and (g◦g), we need to substitute one function into the other and simplify the resulting expression.
(a) (f◦g)(4):
To find (f◦g)(4), we need to first find g(4) and then substitute it into f(x):
g(4) = 7 - 1/2(4)^2
= 7 - 8
= -1
Now we substitute g(4) = -1 into f(x):
(f◦g)(4) = f(g(4))
= f(-1)
= 3(-1)^2 - 2
= 1
Therefore, (f◦g)(4) = 1.
(b) (g◦f)(2):
To find (g◦f)(2), we need to first find f(2) and then substitute it into g(x):
f(2) = 3(2)^2 - 2
= 10
Now we substitute f(2) = 10 into g(x):
(g◦f)(2) = g(f(2))
= g(10)
= 7 - 1/2(10)^2
= -43
Therefore, (g◦f)(2) = -43.
(c) (f◦f)(1):
To find (f◦f)(1), we need to find f(f(1)):
f(1) = 3(1)^2 - 2
= 1
Now we substitute f(1) = 1 into f(x):
(f◦f)(1) = f(f(1))
= f(1)
= 1
Therefore, (f◦f)(1) = 1.
(d) (g◦g)(0):
To find (g◦g)(0), we need to find g(g(0)):
g(0) = 7 - 1/2(0)^2
= 7
Now we substitute g(0) = 7 into g(x):
(g◦g)(0) = g(g(0))
= g(7)
= 7 - 1/2(7)^2
= -17/2
Therefore, (g◦g)(0) = -17/2.