a=60+kar=100+ka(r)'2=150+k (a乘以r的平方)求,a.怎么算哦,
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a=60+kar=100+ka(r)'2=150+k (a乘以r的平方)求,a.怎么算哦,
a=60+k
ar=100+k
a(r)'2=150+k (a乘以r的平方)
求,a.怎么算哦,
a=60+kar=100+ka(r)'2=150+k (a乘以r的平方)求,a.怎么算哦,
a=60+k (1)
ar=100+k (2)
a(r)'2=150+k (a乘以r的平方) (3)
(2)-(1),得a(r-1)=40 (4)
(3)-(2),得ar(r-1)=50 (5)
(5)/(4),得r=5/4
代入(4),求得a=160
a=60+k..............①
ar=100+k............②
ar²=150+k.......③
将①代入②得:(60+k)r=100+k,所以r=(100+k)/(60+k)........④
将②代入③得:ar*r=(100+k)r=150+k.......................⑤
将④代入⑤得:(100+k...
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a=60+k..............①
ar=100+k............②
ar²=150+k.......③
将①代入②得:(60+k)r=100+k,所以r=(100+k)/(60+k)........④
将②代入③得:ar*r=(100+k)r=150+k.......................⑤
将④代入⑤得:(100+k)*(100+k)/(60+k)=150+k,由①知a=60+k
所以上式可以写成:(100+k)²/a=150+k
所以a=(100+k)²/(150+k)
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a=60+k为1式,ar=100+k为2式,ar^2=150+k为3式,1式/2式=1/r=(60+k)/(100+k)为4式,2式/3式=1/r=(100+k)/(150+k)为5式, 4式=5式解k=100代1式得a=160