How do you graph r=10sin4θ?

1 Answer
Aug 10, 2018

See explanation and graph.

Explanation:

0r=10sin4θ[0,10] and the period = 2π4=π2.

As r is non-negative, so is sin4θ, and so,

4θ[π,2π]θ[π4,π2]r0 for

only half of every period.

Four loops are created for

θ[0,π4],[π2,34π].[π,54π]and[32π,74π].

See graph depicting these aspects now, for the converted

equation, using

sin4θ=4(cos3θsinθcosθsin3θ)

(x2+y2)2.5=10(4(x3yxy3))
graph{( x^2 + y^2 )^2.5 - 40 (x^3y - xy^3 ) = 0 [ -20 20 -10 10]}

I think, after reading again and again that scalar r0 in my

answers, the centuries old practice of showing ( 4 r-positive + 4 r-

negative ) 8 loops, for this equation, is given a go.