Trigonometry Question... Rectangular/Polar

Q: Write x^2 - y^2 =1 in polar form

My answer is r= cos^-1(1/2)

Am i right or close to right?

x² - y² = 1

r² cos²Θ - r² sin²Θ = 1

r² (cos²Θ - sin²Θ) = 1

r² (cos 2Θ) = 1

so
..........1
r² = ▬▬▬▬ = sec 2Θ
........cos 2Θ


Your answer has no Θ in it AND cos^(-1)Θ
is not 1/cosΘ, it is inverse cos Θ so your
answer was not close.