How do you convert #8=(4x-11y)^2+3y# into polar form?

1 Answer
Jun 18, 2017

Substitute #x = rcos(theta) and y = rsin(theta)#.

Explanation:

Given #x = rcos(theta) and y = rsin(theta)#, we have
#8 = (4rcostheta - 11rsintheta)^2 + 3rsintheta#

#8 = (r[4costheta - 11sintheta])^2 + 3rsintheta#

#8 = r^2(4costheta - 11sintheta)^2 + 3rsintheta#

We can use FOIL to simplify the expression in parentheses, but it doesn't lead us anywhere "nice."

We could solve for r using the Quadratic Formula if we are required to, but this is positively unfriendly, and the equation is already in a Polar form.