问题
解答题
已知:
(1)
(2)
|
答案
(1)∵
=a 3
=b 5
,设a=3x,b=5x,c=7x,c 7
∴
=a+b+c b
=3;3x+5x+7x 5x
(2))∵
=a 3
=b 5
,设a=3x,b=5x,c=7x,c 7
∴
=a+2b-3c a+c
=-3x+10x-3×7x 3x+7x
.4 5
已知:
(1)
(2)
|
(1)∵
=a 3
=b 5
,设a=3x,b=5x,c=7x,c 7
∴
=a+b+c b
=3;3x+5x+7x 5x
(2))∵
=a 3
=b 5
,设a=3x,b=5x,c=7x,c 7
∴
=a+2b-3c a+c
=-3x+10x-3×7x 3x+7x
.4 5