Find The asymptotes of the curve
\frac{a^2}{x^2}+\frac{b^2}{y^2}=1
solution
\frac{a^2}{x^2}+\frac{b^2}{y^2}=1 \Rightarrow \,b^2x^2+a^2y^2=x^2y^2
equating the coefficient of highest powers of x to zero ,
we\,get\, \;b^2-y^2=0\Rightarrow\;y=\pm b
equating the coefficient of highest powers of y to zero ,
we\,get\, \;a^2-x^2=0\Rightarrow\;x=\pm a
\therefore x=\pm \;a \; and \;y=\pm \;b \; are\; the \;required\;asymptotes
Q-Find out circular asymptotes of the curve
r=\frac{3\theta}{\theta+1}
Solution – the equation of the curve is r=\frac{3\theta}{\theta+1}=f(\theta)\, ,say
\lim_{\theta\rightarrow \infty}f(\theta)=\lim_{\theta\rightarrow \infty}\frac{3\theta}{\theta+1 }=\lim_{\theta\rightarrow \infty}\frac{3}{1+\frac{1}{\theta} }=3
r=3 circular asymptote
Find the asymptotes parallel to the axes of the curve
x^2 y^2 - x^2 - y^2 - x - y + 1 = 0
Given curve is
x^2 y^2 - x^2 - y^2 - x - y + 1 = 0
Given curve is of degree 4 so we cannot have more than 4 asymptotes
Asymptotes parallel to x axis :
Equating the coefficient of highest power of x (i.e,\; of\; x^2 \;) equals to zero,
We get
y^2-1=0 \implies y^2=1 \implies y =\pm1 \\ \implies y-1=0 \; and \; y+1=0
Asymptotes parallel to y axis :
Equating the coefficient of highest power of y (i.e,\; of\; y^2 \;) equals to zero,
We get
x^2-1=0 \implies (x-1)(x+1)=0 \\ \implies x-1=0 \; and \; x+1=0
The asymptotes of the given curve are
{\color{Blue} y-1=0,\;y+1=0,\; x-1=0 \; and \; x+1=0}
keywords
how to find asymptotes of a curve
asymptotes of a curve