How do you graph r^2 = sin2(t)?

1 Answer
Jul 23, 2018

See graphs galore.

Explanation:

The power-scaling of r is done,

when r is changed to r^n, n > 1, in r = f( theta ).

It is r-more, when r in ( 0, 1 ). Otherwise, jt is r-less

Here, this is an example.

Use r = sqrt( x^2 + y^2 ) >= 0, r ( cos theta, sin theta )

and sin 2theta = 2 sintheta cos theta,

to get the Cartesian form of

r^2 = sin 2theta as

( x^2 + y^2 ) ^2 ) - 2xy = 0.

The Socratic graph is immediate.
graph{( x^2 + y^2 ) ^2 - 2xy =0[-2 2 -1 1]}
Graph of r = sin 2theta, for contrast in r-scaling:
graph{( x^2 + y^2 ) ^1.5 - 2xy =0[-2 2 -1 1]}

Easy to see which is which, jn the combined graph, along with the

third graph of r^5 = sin 2theta:

graph{(( x^2 + y^2 ) ^2 - 2xy)( ( x^2 + y^2 ) ^1.5 - 2xy) ( ( x^2 + y^2 ) ^3.5 - 2xy) =0[-2 2 -1 1]}