SOLUTION: HELP!! Please!! Missed lecture and nothing makes sense. The following apply for the listed problems...let f(x)=x+5; let g(x)=X^2-2; let h(x)=-3x 1. ((f)*(g))*x I tried to writ

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: HELP!! Please!! Missed lecture and nothing makes sense. The following apply for the listed problems...let f(x)=x+5; let g(x)=X^2-2; let h(x)=-3x 1. ((f)*(g))*x I tried to writ      Log On


   

Question 60874: HELP!! Please!! Missed lecture and nothing makes sense. The following apply for the listed problems...let f(x)=x+5; let g(x)=X^2-2; let h(x)=-3x
1. ((f)*(g))*x
I tried to write this %28x%2B5%29%2A%28x%5E2-2%29%2Ax and got %28x%5E3-2x%2B5x%5E2-10%29%2Ax+and+then+%7B%7B%7Bx%5E4%2B5x%5E3-2x%5E2-10x and then looked for a gun. I don't know where to go. Are we solving for x or simplifying?
2. h(h(5))
3. g(h(-1))
4. (f*(4)) + (g*(6))
Thanks so much in advance!
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Let f(x)=x+5; let g(x)=X^2-2; let h(x)=-3x
1. ((f)*(g))(x) <---I think this is what you meant.
%28x%2B5%29%28x%5E2-2%29
x%28x%5E2-2%29%2B5%28x%5E2-2%29
x%5E3-2x%2B5x%5E2-10
x%5E3%2B5x%5E2-2x-10
:
2. h(h(5))
First find h(5)
h%285%29=-3%285%29
h%285%29=-15
h(h(5))=h(-15)
Now substitute that value into the h function.
h(h(5))=-3(-15)
h(h(5))=45
:
3. g(h(-1))
h(-1)=-3(-1)
h(-1)=3
g(h(-1))=g(3) Substitute 3 into the g function.
g%28h%28-1%29%29=%283%29%5E2-2
g(h(-1))=9-2
g(h(-1))=7
:
4. (f(4)) + (g(6))
%28%284%29%2B5%29%2B%28%286%29%5E2-2%29
(4+5)+(36-2)
9+34
43
:
Happy Calculating!!!