1.

The line lx + my + n = 0 is a normal to the ellipse \(\frac{{{x^2}}}{{{a^2}}} + \frac{{{y^2}}}{{{b^2}}} = 1\) if

A. \(\frac{{{a^2}}}{{{l^2}}} - \frac{{{b^2}}}{{{m^2}}} = \frac{{{{\left( {{a^2} - {b^2}} \right)}^2}}}{{{n^2}}}\)
B. \(- \frac{{{a^2}}}{{{l^2}}} - \frac{{{b^2}}}{{{m^2}}} - \frac{{{{\left( {{a^2} - {b^2}} \right)}^2}}}{{{n^2}}} = 0\)
C. \(\frac{{{a^2}}}{{{l^2}}} + \frac{{{b^2}}}{{{m^2}}} = \frac{{{{\left( {{a^2} - {b^2}} \right)}^2}}}{{{n^2}}}\)
D. \(\frac{{{a^2}}}{{{l^2}}} + \frac{{{b^2}}}{{{m^2}}} + \frac{{{{\left( {{a^2} - {b^2}} \right)}^2}}}{{{n^2}}} = 0\)
Answer» D. \(\frac{{{a^2}}}{{{l^2}}} + \frac{{{b^2}}}{{{m^2}}} + \frac{{{{\left( {{a^2} - {b^2}} \right)}^2}}}{{{n^2}}} = 0\)


Discussion

No Comment Found