Porisma
All chapter practice

Conic sections

Practice section 2 of 2

Questions 7–11 in this collection

Practice questions

Discussion practice · 2 of 5

Six conics: complete the square and identify graph features

Sketch the following without the use of a graphic calculator, indicating clearly any axial intercepts, asymptotes, vertices/turning points and lines of symmetry.

(a) x2+x−3y=2x^2+x-3y=2

(b) y2+y−3x=2y^2+y-3x=2

(c) a2x2+b2y2=r2a^2x^2+b^2y^2=r^2, a>b>0a>b>0 and r>0r>0

(d) x2+4y2+4x−8y+4=0x^2+4y^2+4x-8y+4=0

(e) 36y2=4x2+136y^2=4x^2+1

(f) x2−4y2−2x−8y−39=0x^2-4y^2-2x-8y-39=0

CJC · Discussion · Question 1

Solution

Discussion practice · 4 of 5

Rational curve and ellipse: exactly two intersections

Sketch the graph of y=2x(x−μ)y=\dfrac2{x(x-\mu)}, where μ\mu is a positive constant, indicating clearly any axial intercept(s), asymptote(s) and coordinates of turning point(s).

Given a=μ2a=\dfrac\mu2, deduce the range of values of bb in terms of μ\mu, such that the graphs of b(x−a)2+a2y2=a2bb(x-a)^2+a^2y^2=a^2b and y=2x(x−μ)y=\dfrac2{x(x-\mu)} intersect twice, where aa and bb are positive real numbers.

[2010/NJC/Promo/6]

CJC · Discussion · Question 3

Solution

Discussion practice · 5 of 5

Rational curve: coefficients, hyperbola comparison and stationary points

The curve CC has equation y=ax2+bx+cx−1y=\dfrac{ax^2+bx+c}{x-1}, where aa, bb and cc are non-zero constants.

(a) It is given that CC passes through the point (3,23/2)(3,23/2) and has a minimum point at (2,10)(2,10).

(i) Find the values of aa, bb and cc.

(ii) Sketch CC, giving the coordinates of any turning points, points of intersection with the axes and the equations of any asymptotes.

(iii) Find the set of values of m/km/k, where mm and kk are positive constants, such that the curve with equation x2k2−(y−1)2m2=1\dfrac{x^2}{k^2}-\dfrac{(y-1)^2}{m^2}=1 does not intersect CC.

(b) In the case when a=−1a=-1 and b=−1b=-1, find the set of values of cc, where c≠2c\ne2, such that CC has no stationary point.

[2013/VJC/II/2]

CJC · Discussion · Question 4

Solution

Back to all practice questions