For the function f defined by f(x) = 3x/x^2+4. find the following values.

Question

(a) f(-5) =

(b) f(-x) =

(c) -f(x) =

Answer 1

Solution: First, I am assuming the function is as written f(x) = (3x / x²+4) and not (3x/x²)+4. with that:

f (-5) = { (3)(-5)] / [(-5)² + 4] } , f(-5) = [ -15 / ( 25+4) ] = -15 / 29

f(-x) = { (3)(-x) / [ (-x)² +4] } = -3x / ( x² +4)

-f(x) = - (3x / x² +4) = -3x / ( x² + 4) , and so for this function f(-x) = -f(x)

Answer 2

The question is not clear:

1) Is it: f(x) = (3x)/(x^2) + 4 (The way it is written, this is the correct interpretation; but I don't think this is the intend as we can divide by x and write it as: f(x) = (3)/(x) + 4.

2) Is it: f(x) = (3x)/(x^2+4).

The answers depend. First, we need to have precise clear question.