maths 問題
2008-10-03 4:48 am
if on root of kx - 3x^2 = 10 is 2, find the value of k and the other root
回答 (2)
2008-10-03 5:32 am
✔ 最佳答案
kx - 3x2 = 10sub x = 2,
2k - 3(2)2 = 10
k = (10+12)/2 = 11
.'. eqt : 3x2 - 11x + 10 = 0
(3x-5)(x-2) = 0
x = 5/3 or 2
2008-10-03 4:59 am
if on root of kx - 3x^2 = 10 is 2,
then k(2)-3(2)^2=10=>k=16
so 16x-3x^2=10
sum of roots = -(16/-3)=-16/3
so the other root is -16/3-2=-22/3//
2008-10-03 16:11:32 補充：
so the other root is 16/3-2=10/3//
then k(2)-3(2)^2=10=>k=16
so 16x-3x^2=10
sum of roots = -(16/-3)=-16/3
so the other root is -16/3-2=-22/3//
2008-10-03 16:11:32 補充：
so the other root is 16/3-2=10/3//
收錄日期: 2021-04-13 16:08:01
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081002000051KK01905