SOLUTION: Let f(x)=x^2−4 and g(x)=4x+1, evaluate the following. a. f(−4) = b. f(−1)+g(−1) = c. 3f(x)−g(x) = d. f(g(4)) = e. g(f(4)) =

Algebra ->  Expressions-with-variables -> SOLUTION: Let f(x)=x^2−4 and g(x)=4x+1, evaluate the following. a. f(−4) = b. f(−1)+g(−1) = c. 3f(x)−g(x) = d. f(g(4)) = e. g(f(4)) =      Log On


   

Question 923330: Let f(x)=x^2−4 and g(x)=4x+1, evaluate the following.
a. f(−4) =
b. f(−1)+g(−1) =
c. 3f(x)−g(x) =
d. f(g(4)) =
e. g(f(4)) =
Found 2 solutions by ewatrrr, MathLover1:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=x^2−4 and g(x)=4x+1
Plug and Play
a. f(-4) = 12
b. f(−1)+g(−1) = -3 -3 = -6
c. 3f(x)−g(x) = 3(x^2 - 4) - (4x+1) = 3x^2 - 4x - 13
d. f(g(4)) = f(17) = 285
e. g(f(4)) = g(12) = 49

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

Let f%28x%29=x%5E2-4 and g%28x%29=4x%2B1, evaluate the following.
a.+f%28-4%29 =
f%28-4%29=%28-4%29%5E2-4
f%28-4%29=16-4
f%28-4%29=12

b.

c. 3f%28x%29-g%28x%29+=3%28+x%5E2-4%29-%284x%2B1%29=3x%5E2-12-4x%2B1=3x%5E2-4x-11

d. f%28g%284%29%29 =
first find g%284%29
g%284%29=4%2A4%2B1=17
now find f%2817%29
f%2817%29=17%5E2-4=289-4=285
so,f%28g%284%29%29=285

e. g%28f%284%29%29 =
f%284%29=4%5E2-4=16-4=12
g%2812%29=4%2A12%2B1=49
g%28f%284%29%29=49