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Edexcel C3

Question:

Sketch the graphs of y= x^2 - 4 and y=/ x^2 - 4/, indicating the points where the graphs meet the x-axis and the y-axis.

Do those brackets in second equation mean that anything which would be negative on a graph has to be reflected in positive direction?

And how do I chose values for x...please could anybody help to explain me this, as I really have no idea about doing this questions...we didn`t do a lot about it in college.

Thank you very much. :smile:

Reply 1

Matty919

first graph crosses x at 2 at -2 and y at -4.

second does indeed reflect all negative y to positive.

... I think.

Reply 2

FZka

For y= x^2 - 4
Draw the graph of y=x^2 and shift it vertically by 4 units in the negative direction. (Simple transformation)

For y=|y= x^2 - 4| means you have to reflect all values of y<0 in the x-axis.

To find points of intersection with the y-axis let x=0 and solve.
To find points of intersection with the x-axis let y=0 and solve.