We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.

This is the graph for the function f(x) = -x2 + 2. 

a. The graph of f gets multiplied with the factor - 1/2 to create the graph g. How would the graph of function g look like and what would the function notation be?

b. The graph of the function h(x) = 7x2 + b starts from the graph of f by multiplying it with a factor. Calculate the value of b.


 Jun 11, 2019

a) i'm not really sure what you mean by factor, and function of g, so please be a little more clear and i could answer your question :)
b) a tip would be to imagine this as slope intercept form. How would you find the y intercept of an equation? first you would need to plug a point in and then leave b as a variable and solve for it.
Again, I'm sorry I couldn't give you the answers to this, but if you have further questions or would like to clarify what the question is asking please reply to this, and I will be more than happy to help! :) 
sorry again. 

 Jun 11, 2019

Oops sorry! English isn't my native tongue so I'm kinda awful at translating the question. Like the graph of f gets multiplied with - 1/2 in/from the x axis and this new graph is the graph for function g. If you still don't understand, don't worry, I already appreciate the intention :)

Guest Jun 11, 2019
edited by Guest  Jun 11, 2019


If you take the graph of  f  and multiply the y-coordinates of every point by  \(\frac12\) , that will vertically compress the graph


If you take the graph of  f  and multiply the y-coordinates of every point by  -1 , that will reflect the graph over the x-axis.


So the graph of function  g  is the graph of function  f  vertically compressed and reflected over the x-axis.


I'm not entirely sure what the function notation is, but I think it is this:


g(x)  =  -\(\frac12\) f(x)


(Also........I wanted to say "vertically compressed by a factor of  2" or "vertically compressed by a factor of  \(\frac12\) " but I didn't know which is considered correct, and the only thing I could find about this question was here: http://mathforum.org/library/drmath/view/77603.html. It seems like there's not a universally accepted way of stating it, so I just left it out!)



f(x)  =  -x2 + 2

h(x)  =  7x2 + b


We can see the factor must be  -7  .


h(x)  =  -7 f(x)  =  -7( -x2 + 2 )  =  7x2 - 14


h(x)  =  7x2 - 14     so we can see that     b = -14

 Jun 11, 2019

18 Online Users