Page 52 - More Higher algebra

Example 9:

Plotting implicit functions. Here is an example of an

implicit function,

2
2
+ + = 4
As you can see you cannot get all y on the left hand
side or all x on the right hand side. You can however

treat this as a quadratic function in y, therefore,
2
2
+ ( ) + ( − 4) = 0

Using the well equation for finding roots of a
quadratic,

2
2
− ± √ − 4( − 4)
=
2
or

− ± √16 − 3 2
=
2

2
For the values of y to be real, then 3 ≤ 16. Or
4
≤ = 2.309
√3
To generate a table, use the TABLE feature in your fx

calculator (w7). Once you see f(X) = , enter the

following keystrokes,

48