PARABOLA..........please help.

VITEEE 2015 Help › Co-ordinate Geometry questions › PARABOLA..........please help.

Chord of contact of pair of tangents drawn from , each point on the line
2x+y=4 , to the parabola y²=4x pass through which fixed point??

#Mathematics #Co-ordinate Geometry

UP 0 DOWN 0 0 5
Post on FacebookPost anonymously?

5 Answers

Sonne ·Jun 13 '10 at 2:13

the equation of chord of contact to a parabola from a point x₁,y₁ is
$y y 1 - 2 (x + x 1 ) = 0$
now we make a constraint relationship on $x 1 a n d y 1 $
i.e

y₁=4-2x₁

$y(2-x_1)-x-x_1=0\\ 2y-x-x_1(y+1)\\$

so the answer is

(-2,-1)

UP 0 DOWN 0
Post on FacebookPost anonymously?

sanchit ·Jun 13 '10 at 2:17

hey can u plzz temme how u solved the eq.n 2y-x-x₁(y+1)=0.i reached here but wasn't able to proceed[2][2][2][2]

UP 0 DOWN 0
Post on FacebookPost anonymously?

Sonne ·Jun 13 '10 at 2:20

its repesenting the family of lines passing thru the intersection of lines

2y-x=0
and
y=-1

its of form
L₁+Î»L₂=0
where Î» is a parameter
here x₁ is parameter

UP 0 DOWN 0
Post on FacebookPost anonymously?

Joydoot ghatak ·Jun 15 '10 at 4:59

thanx.... for the soln...

but the answr is given as (-2,1)

UP 0 DOWN 0
Post on FacebookPost anonymously?

sahil jain ·Oct 1 '10 at 8:21

(-2,-1)

UP 0 DOWN 0
Post on FacebookPost anonymously?

Your Answer

Basic Integral Calculus Operators Symbols Matrix Cases

√ √ || {} [] () → ~ ^ x x x → → ln log lg lim lim cos sin tan cot arcsin arccos arctan

∫ ∫ ∫ ∫ ∫ ∬ ∬ ∬ ∬ ∬ ∭ ∭ ∭ ∭ ∭ ⨌ ⨌ ⨌ ⨌ ⨌

∑ ∑ ∑ ∑ ∑ ∮ ∮ ∮ ∮ ∮ ∏ ∏ ∏ ∏ ∏ ∐ ∐ ∐ ∐ ∐

+ - × ÷ ± ∓ = ∪ ∩ ≠ ∼ ≈ ∅ ∀ ∃ ∈ ∋ ∝ ≤ ≥ ≃ ≅ ≡ < > ≪ ≫ ⊂ ∉ ⊃ ⊆ ⊇ ⇒ ⇐ ⇔ ⇒ ⇐ ⇔ ⇑ ⇓ ⇕ → ← ↔ → ← ↔ ↑ ↓ ↕ ↖ ↗ ↘ ↙ ↪ ↩ ⇀ ↼ ⇁ ↽

° ∂ ∞ α β γ δ θ λ μ ν ξ π ρ σ φ ω ε ƒ κ τ υ Γ Δ Λ Σ Π Ω

Close [X]

PARABOLA..........please help.

5 Answers

Your Answer

Add Image

Similar Questions