How is the graph of #h(x)=3+5/2x^2# related to the graph of #f(x)=x^2#?

1 Answer
Feb 12, 2017

The two functions when compared to each other on a graph constitute (or make) a straight line.

Explanation:

Consider the equation #h(x)=3+5/2x^2#
and the equation #g(x)=x^2#

Notice any terms which seem to be present in both equations?

The "#x^2#" term is present in both terms. While #h(x)# has another term (which is not a variable but a constant), #g(x)# is defined only by the term #x^2#.

So if we replace the #x^2# in the equation of #h(x)# with #g(x)#, we get

#h(x)=3+5/2g(x)#

Now, what's the equation for a straight line? Simple, it's

#y=c+mt# (usually #x# is written but I'm using #t# to avoid a confusion which will arise at first glance)

Notice anything similar between the two equations I just wrote down? Well, let's make it more simple to view then.

Well, if we took #h(x)=y# and #g(x)=t#

Now, it'll become #y=3+5/2t#

So there you have it. The functions #h(x)# and #g(x)# relate to each other as if they make a straight line.

Here's how they'll look if we drew them
graph{3+5/2x [-10, 10, -5, 5]}