2a^2-3ab-5b^2=0,则(2a-b)/(3a+2b)=

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2a^2-3ab-5b^2=0,则(2a-b)/(3a+2b)=

2a^2-3ab-5b^2=0,则(2a-b)/(3a+2b)=
2a^2-3ab-5b^2=0,则(2a-b)/(3a+2b)=

2a^2-3ab-5b^2=0,则(2a-b)/(3a+2b)=
2a^2-3ab-5b^2=0
(a+b)(2a-5b)=0
a=-b或a=5b/2
a=-b时
(2a-b)/(3a+2b)=(-3b)/(-b)=3
a=5b/2
(2a-b)/(3a+2b)=(4b)/(19b/2)=8/19

2a^2-3ab-5b^2=0
(a-b)(2a+5b)=0
所以a-b=0或2a+5b=0
a=b或a=-5b/2
若a=b
(2a-b)/(3a+2b)
=(2b-b)/(3b+b)
=b/4b
=1/4
若a=-5b/2
(2a-b)/(3a+2b)
=(-5b-b)/(-15b/2+2b)
=-6b/(-11b/2)
=12/11

2a^2-3ab-5b^2=(2a-5b)(a-b)=0
则a=5b/2或a=b
当a=5b/2时 (2a-b)/(3a+2b)=(5b-b)/(19b/2)=8/19
当a=b时 (2a-b)/(3a+2b)=1/5