1.If f(x)=3+kx^2,g(x)=2x and f(-2)=-1,find
(a)the value of k
(b)the values of x such tht f(x)=g(x)
2.Consider f(x)=x^2-3x+1 and g(x)=7+2x.Find the values of x such
that f(x+1)=g(3x)
f4 maths
2009-04-10 11:33 pm
回答 (1)
2009-04-10 11:55 pm
✔ 最佳答案
1(a) f(-2)=-1
∴3+k(-2)2=-1
4k=-4
∴k=-1//
(b)
f(x)=g(x)
∴3-x2=2x
x2+2x-3=0
(x+3)(x-1)=0
x=-3 or x=1//
2.
f(x+1)=g(3x)
(x+1)2-3(x+1)+1=7+2(3x)
x2+2x+1-3x-3+1=7+6x
x2-7x-8=0
(x-8)(x+1)=0
∴x=8 or x=-1//
收錄日期: 2021-04-23 20:39:10
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090410000051KK01043