Verified Solution • 2025–26 Session moderate

QJEEAdv08Mafaba: JEE Advanced 2008 Mathematics - Class 11 JEEAdv08Mafaba Solution: Consider a branch of the hyperbola with vertex at the point .…

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with vertex at the point AA . Let BB be one of the end points of its latus rectum. If CC is the focus of the hyperbola nearest to the point AA , then the area of the triangle ABCABC is

Multiple Choice Options

  • A 1−231 - \sqrt {{2 \over 3}}
  • B 32−1\sqrt {{3 \over 2}} - 1
  • C 1+231 + \sqrt {{2 \over 3}}
  • D 32+1\sqrt {{3 \over 2}} + 1

Step-by-Step Verified Solution

We have,

x2−2y2−22x−42y−6=0{x^2} - 2{y^2} - 2\sqrt 2 x - 4\sqrt 2 y - 6 = 0

(x−2)24−(y+2)22=1{{{{(x - \sqrt 2 )}^2}} \over 4} - {{{{(y + \sqrt 2 )}^2}} \over 2} = 1

a=2,b=2a = 2,b = \sqrt 2

⇒e=32\Rightarrow e = \sqrt {{3 \over 2}}

Now, e=a2+b2a2=32e = \sqrt {{{{a^2} + {b^2}} \over {{a^2}}}} = \sqrt {{3 \over 2}}

Area, =12= {1 \over 2} ×\times Base ×\times Height

=12a(e−1)b2a= {1 \over 2}a(e - 1){{{b^2}} \over a}

=12(3−2)×22= {1 \over 2}{{(\sqrt 3 - \sqrt 2 ) \times 2} \over {\sqrt 2 }}

=3−22= {{\sqrt 3 - \sqrt 2 } \over {\sqrt 2 }}

=(32−1)= \left( {\sqrt {{3 \over 2}} - 1} \right)

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