change rectangular equations to polar equations

Question

y^2=10x

 

make sure its in polar equations

Answer 1

x = rcosθ and y = rsinθ

 

So, y² = 10x can be written as r²sin²θ = 10rcosθ

 

                                               rsin²θ = 10cosθ

 

                                                      r = 10cosθ/sin²θ

 

                                                      r = 10(cosθ/sinθ)(1/sinθ)

 

                                                      r = 10cotθcscθ