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  x=r cos `theta` y=r sin `theta` `x^(2)` +`y^(2)` =`r^(2)` use above data to rewrite...

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x=r cos `theta`

y=r sin `theta`

`x^(2)` +`y^(2)` =`r^(2)`

use above data to rewrite the expressions in trignomtric form



y= -2x+3

`(x-2)^(2)` +`y^(2)` =4



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Posted (Answer #2)

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(1) Convert y=2 into polar form:

`sintheta=y/r ==> y=rsintheta`

So `rsintheta=2 ==> r=2/sintheta` or `r=2csctheta`

(2) Convert `y=1/4x^2` into polar form:

`x=rcostheta, y=rsintheta` so


`rsintheta=1/4 r^2 cos^2theta`


`r=(4sintheta)/(cos^2theta)` or `r=4tanthetasectheta`

(3) Convert y=-2x+3 into polar form:





(4) Convert `(x-2)^2+y^2=4` into polar form:


`x^2+y^2-4x=0`   but `x^2+y^2=r^2` so:




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