請詳細步驟教我計以下三條 :
(不要網址回答)
1. it is given that y varies directly as the square rood of x. when x=16 y=1. find the value of y when x=36
我計到 x=9. 但答案是3/2 ??
2. It is given that P varies directly as Q. If Q increase to 2 times the original value, by how many times the original value is P ?
3. It is given that s varies directly as t. When t=12, s=36, If t increase by 1, what is the increase or decrease in s ?
急 ! F5 變分計法 7q01
2012-08-27 2:46 am
回答 (1)
2012-08-27 8:33 am
✔ 最佳答案
1. y varies as √x ( varies as 打不到那符號)y=k√x (k ≠ 0)
1=k√16
k=1/4
∴y=√x/4
=√36/4
= 6/4
=3/2
2.P varies as Q
P=kQ (k ≠ 0)
Let P1, Q1 be the new values of P, Q resp.
P1=kQ1
= k(2Q)
=2kQ
=2P
∴P is 2 times than orginal value
3.s varies t
s=kt(k ≠ 0)
36=12k
k=3
∴s=3t
:Let s1,t1 be the new values of s and t resp.
s1=3t1
=3(t+1)
=3t+3
=s+3
∴The increase in s is 3
參考: me
收錄日期: 2021-04-13 18:56:39
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120826000051KK00534