已知1/a+1/b=4,求(4a+3ab+4b)/(-3a+2ab-3b)的值

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已知1/a+1/b=4,求(4a+3ab+4b)/(-3a+2ab-3b)的值已知1/a+1/b=4,求(4a+3ab+4b)/(-3a+2ab-3b)的值已知1/a+1/b=4,求(4a+3ab+4

已知1/a+1/b=4,求(4a+3ab+4b)/(-3a+2ab-3b)的值
已知1/a+1/b=4,求(4a+3ab+4b)/(-3a+2ab-3b)的值

已知1/a+1/b=4,求(4a+3ab+4b)/(-3a+2ab-3b)的值
1/a+1/b=4
(a+b)/ab=4
a+b=4ab
(4a+3ab+4b)/(-3a+2ab-3b)
=[4(a+b)+3ab]/[-3(a+b)+2ab]
=(16ab+3ab)/(-12ab+2ab)
=19ab/(-10ab)
=-19/10

(4a+3ab+4b)/(-3a+2ab-3b)
= (4/b+3+4/a)/(-3/b+2-3/a)
= (4*4+3)/(2-3*4)
= -19/10

1/a+1/b=4 a+b=4ab
(4a+4b+3ab)/(-3a-3b+2ab)
=19ab/-10ab
=-19/10