作业帮分离常数法求值域的问题
来源：学生作业帮 编辑：作业帮 分类：数学作业 时间：2024/05/06 19:47:34
分离常数法求值域的问题
1.f(x)=-2x+3/(x+1)
2.f(x)=4x+2/(3x+1) x∈[-2,-1/3)∪(-1/3,3)
1.f(x)=-2x+3/(x+1)
2.f(x)=4x+2/(3x+1) x∈[-2,-1/3)∪(-1/3,3)
1.f(x)=-2x+3/(x+1)=[-2(x+1)+5]/(x+1)=-2+5/(x+1)
f(x)≠-2
2.f(x)=4x+2/(3x+1) =[4/3(3x+1)+2/3]/(3x+1) =4/3+2/3/(3x+1)
f(x)≠4/3 x∈[-2,-1/3)∪(-1/3,3)
f(x)∈[ 4/3+2/3/(3(-2)+1) ,4/3)∪( 4/3,4/3+2/3/(3(3)+1) )
f(x)≠-2
2.f(x)=4x+2/(3x+1) =[4/3(3x+1)+2/3]/(3x+1) =4/3+2/3/(3x+1)
f(x)≠4/3 x∈[-2,-1/3)∪(-1/3,3)
f(x)∈[ 4/3+2/3/(3(-2)+1) ,4/3)∪( 4/3,4/3+2/3/(3(3)+1) )