1.若X.Y的關係為Y=6-2X,則y與[x+a]成正比,x與[y+b]成正比 求a.b
2.設[y+1]隨著[x-2]成正比,當x=3時,y=4,則y=9時,x=?
2006-04-17 14:29:19 · 3 個解答 · 發問者 Anonymous in 科學 ➔ 數學
１.y = 6-2x∵y與x+a成正比∴(6-2x)/(x+a) = k6-2x = kx+ax6/x-2-k = a∵x與y+b成正比∴x/(6-2x+b) = rx = 6r-2rx+brx/r-6-2x = b２.∵y+1與x-2成正比∴(y+1)/(x-2) = k又x = 3，y = 4，∴k = 5y = 9代入(y+1)/(x-2) = 5，得x = 4
2006-04-17 14:42:43 · answer #1 · answered by smallwhite 7 · 0⤊ 0⤋
真是的!數學最重要是要懂
你只求答案不會算法過程<
換個數字再考一次你依然不會
學數學不應該這種態度的
2006-04-17 18:21:30 · answer #2 · answered by 橘橘 * 3 · 0⤊ 0⤋
2. [y+1]/[x-2]=k
x=3 , y=4 ==> k=5
y=9 時 x=4
2006-04-17 14:37:58 · answer #3 · answered by panadol 1 · 0⤊ 0⤋