Question

求下列函数的自变量取值范围

y=3x-1
y=1/x+2
y=根号x-2
b=三次根号a-1/5

Answer 1

y=3x-1,自变量取值范围x∈R
y=1/(x+2),x+2≠0,自变量取值范围x≠-2
y=√(x-2),x-2≥0,自变量取值范围x≥2
b=³√a-1/5,自变量取值范围a∈R

Answer 2

y=3x-1,x∈R
y=1/x+2,x+2≠0,x≠-2
y=根号x-2,x-2>=0,x>=2
b=三次根号a-1/5,a∈R