Question

How do you convert `2=(8x-7y)^2-7x` into polar form?

Answer 1

`=>(15sin^2theta-56sin2theta+49)r^2-2=0`

Explanation:

put `x=rcostheta,y=rsintheta` and solve
`2=(8x-7y)^2-7x`
`=>2=64x^2+49y^2-112xy-7x`
`=>2=49(x^2+y^2)+15x^2-7x-xy`
`=>2=49r^2(sin^2theta+cos^2theta)+15r^2sin^2theta-56.2r^2sinthetacostheta`
`=>2=49r^2+15r^2sin^2theta-56r^2sin2theta`
`=>(15sin^2theta-56sin2theta+49)r^2-2=0`