How do you find the asymptotes for #h(x) = sqrt(x^2-3x) - x#?

1 Answer
Sep 18, 2017

#2y+4x-3=0# and #y=-3/2#

Explanation:

#h(x)=y=sqrt(x^2-3x)-x#
#y+x=sqrt(x^2-3x#
Square both side
#(y+x)^2=x^2-3x#
#y^2+2xy+x^2=x^2-3x#
#y^2+2xy+3x=0#

Let equation of Asymptote is #y=mx+c#

Put x=1 and y=m in the terms of highest power (2) of equation of Curve

#phi_2(m)=m^2+2m#
Put x=1 and y=m in the terms of power 1
#phi_1(m)=3#
differentiate with respect to m of #phi_2(m)#
#phi'_2(m)=2m+2#

To find values of m
#phi_2(m)=0#
#impliesm^2+2m=0#
#impliesm(m+2)=0#
either #m=0 or m=-2#

Value of #c=-(phi_1(m))/(phi'_2(m))=-3/(2m+2)#

for #m=0#, #c=-3/2#
Asymptotes are
#y=0x+(-3/2)# or #y=-3/2#

and for #m=-2#, #c=3/2#

Asymptotes are
#y=-2x+3/2# or #2y+4x-3=0#