parametrics question (2 Viewers)

[sadpwner]

Show that x = a+r cos θ, y = b+r sin θ defines a circle with centre (a, b) and radius r.

How do I form an equation out of this?

 

[photastic]

Square x and y and you will cancel out the trig circle identity.

 

[sadpwner]

i tried squaring both sides, but don't really know what to do afterwards. I tried subbing in using the pythag identity tho

 

[photastic]

 

[faisalabdul16]

Yeap

i tried squaring both sides, but don't really know what to do afterwards. I tried subbing in using the pythag identity tho

When you get asked a question which has cos or sin, always make them the subject and square them. After squaring them, you add them. Then you use the trig identity, sin squared theta + cos square theta = 1

 

[meggles_]

Yeap



When you get asked a question which has cos or sin, always make them the subject and square them. After squaring them, you add them. Then you use the trig identity, sin squared theta + cos square theta = 1

Super important identity - many trig questions depend on this identity

Pls memorise

 

[Thank_You]

That trig identity is universal, should of been one of the first identities you memorised!

 

[faisalabdul16]

That trig identity is universal, should of been one of the first identities you memorised!

True

 

[integral95]

got it memorised?

 

[sadpwner]

lol i knew the identities. I just didn't know you just add trig parametrics together rather than subbing in.

 

[photastic]

lol i knew the identities. I just didn't know you just add trig parametrics together rather than subbing in.

I hope my working out helped you though :S