x2 |
a2 |
y2 |
b2 |
∵點(diǎn)P(5,2)在橢圓上,∴2a=|PF1|+|PF2|=
(5+6)2+22 |
(5-6)2+22 |
5 |
∴a=3
5 |
故所求橢圓的標(biāo)準(zhǔn)方程是
x2 |
45 |
y2 |
9 |
(2)由MF1⊥MF2得,
∴
MF1 |
MF2 |
x | 20 |
y | 20 |
即xo2=36-y02,代入橢圓方程得:
yo2=
9 |
4 |
故 y0=±
3 |
2 |
x2 |
a2 |
y2 |
b2 |
(5+6)2+22 |
(5-6)2+22 |
5 |
5 |
x2 |
45 |
y2 |
9 |
MF1 |
MF2 |
x | 20 |
y | 20 |
9 |
4 |
3 |
2 |