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Reply 1
Not sure theta = pi/4?

[because as theta --> pi / 4, r ---> inf?]
normally theta is defined within a range
Reply 3
did you use limits or what to find it
basically the values which would cause r to become infinite

if you meant
Unparseable latex formula:

$[br]2r^2=\tan (2 \theta)



then those would be π4\frac{\pi}{4}, 3π4\frac{3\pi}{4}, 5π4\frac{5\pi}{4}, 7π4\frac{7\pi}{4}
Reply 5
I am sorry but How did you get it,can you tell me the process
Reply 6
Sketch a tan graph. When does it have asymptotes? Now sketch a tan(2theta) graph, when does it have asymptotes?
Reply 7
roshanhero
I am sorry but How did you get it,can you tell me the process


Maybe this will help,

2r2=tan2x2r^2=tan2x
so
2r2=2tanx1tan2x2r^2=\frac{2tanx}{1-tan^2x}

If tan^2x=1 the expression is undefined, this occurs when x=(pi/4)+kpi/2 for k=0,1,2...n a positive integer. Similar to if x=0, lnx is undefined and so there is a asymptote there.
Reply 8
So basically does it means that when "r" tends to infinity,there is asymptote.How can we picturise it graphically.Can you post some graph of it as well,pls.
Reply 9
roshanhero
So basically does it means that when "r" tends to infinity,there is asymptote.How can we picturise it graphically.Can you post some graph of it as well,pls.


Well r represents the distance of the point of the curve from the pole, so if r tends to infinity, it gets greater and greater and closer and closer to the line θ=α\theta = \alpha (where α\alpha is the angle of the point for which r is undefined), and any line which a curve grows arbitrarily close to without ever touching it is, by definition, an asymptote.
I have just quickly composed a graph using a plotter, which can be found in the attachment (sorry for its very large size!).

An explanation

Reply 11
Thanks a lot for all your help,now I get it.Here is the second question.
find the asymptote of
r^2cos2(theta)=a^2
If I plug in cos2(theta) equals zero,I would get r=infinity,so does it means that I would get asymptote at theta=45 degrees.
Reply 12
Can we have some posts here.
Reply 13
hey all
Reply 14
Yes
Reply 15
What about when tan2θ<0\tan{2\theta} < 0?
Reply 16
n1r4v
Yes

But the answer is different.
Reply 17
What's the answer.
Reply 18
We have been teached to find the asymptotes of polar curve by using formula-
Rsin(q -a )=1/f'(a )

Where a denotes the roots of f (q )=0

I appiled it but failed.

Can we show me how to do it by using this formula.
roshanhero
We have been teached to find the asymptotes of polar curve by using formula-
Rsin(q -a )=1/f'(a )

Where a denotes the roots of f (q )=0

I appiled it but failed.

Can we show me how to do it by using this formula.


you may be good at Math but you're not very good at English!