normal to ellipse

the no. of normals that can be drawn to curve 4x²+9y²=36 from an external point in general is
ans-4 explain

1 Answers

eqtn of a normal is given by

y=mx+c

c²=m²(a²-b²)² / {a²+b²m²}

when u substitute c in here.. u will find that the equation is a 4th degree polynomial in m!

so there can be 4 roots in general!

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