Show that the are of the triangle formed by the lines y=m1 x, y=m2 x and y = c is equal to c24 (√33+√11), where m1,m2 are the roots of the equation x2+(√3+2)x+√3−1=0.
y=m1 x, y=m2 x and y=c
Vertices of triangle formed by above lines are
A(0,0), B(cm1,c), C(cm2,c)
So Area of triangle when three vertices are given is
=12∣∣ ∣ ∣∣001cm101cm201∣∣ ∣ ∣∣
=12{x1 (y2−y3)+x2 (y3−y1)+x3 (y1−y2)}
=12[∣∣c2m1−c2m2∣∣]=c22[∣∣m2−m1m1m2∣∣]
Given m1 and m2 are roots of
x2+(√3+2)x+√3−1=0
Product of roots=m1m2=√3−1
|m1−m2|=√(m2+m1)2−4m1m2
=√(√3+2)2−4√3+4 .
|m2−m1|=√3+4+4√3−4√3+4=√11
Area=c22[√11√3−1]
Rationalising denominator gives
c24[√33+√11]
Hence proved.