SOLUTION: If f(x)=-4x^2 and g(x)=2/x, find [g ° f](x) Thank you so much!!!!! God Bless and Happy New Year!!!!!

Algebra ->  Rational-functions -> SOLUTION: If f(x)=-4x^2 and g(x)=2/x, find [g ° f](x) Thank you so much!!!!! God Bless and Happy New Year!!!!!      Log On


   

Question 389755: If f(x)=-4x^2 and g(x)=2/x, find [g ° f](x)
Thank you so much!!!!!
God Bless and Happy New Year!!!!!
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
Given f%28x%29+=+-4x%5E2 and g%28x%29+=+2%2Fx,
to find: %28+f+o+g%29%28x%29
In this case, I am not trying to find a certain numerical value. Instead, I am trying to find the formula that results from plugging the formula for g(x) into the formula for f(x). I will write the formulas at each step, using parentheses to indicate where the inputs should go:
%28+f+o+g%29%28x%29+=+f+%28g%28x%29%29
= f+%282%2Fx%29
= -4%28+___++%29%5E2 ... setting up to insert the input formula
= -4%282%2Fx+%29%5E2
= -4%284%2Fx+%5E2%29
= -16%2Fx+%5E2....or...-16%281%2Fx+%5E2%29