椭圆x^2/a^2+y^2/b^2=1(a大于b大于0)的左右焦点为F1F2若角pf1f2=75度,角PF2F1=15度则b/a=
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椭圆x^2/a^2+y^2/b^2=1(a大于b大于0)的左右焦点为F1F2若角pf1f2=75度,角PF2F1=15度则b/a=
椭圆x^2/a^2+y^2/b^2=1(a大于b大于0)的左右焦点为F1F2若角pf1f2=75度,角PF2F1=15度则b/a=
椭圆x^2/a^2+y^2/b^2=1(a大于b大于0)的左右焦点为F1F2若角pf1f2=75度,角PF2F1=15度则b/a=
由题意得知,F1P垂直于F2P,
即:PF1^2+PF2^2=F1F2^2
(PF1+PF2)^2-2PF1*PF2=(2c)^2
(2a)^2-F1F2*sin15*F1F2*sin75=4c^2=4(a^2-b^2)
(a^2-b^2)sin15sin75=b^2
(a^2-b^2)*(-1/2)(cos90-cos60)=b^2
a^2-b^2=4b^2
a^2=5b^2
(b/a)^2=1/5
b/a=根号5/5