f(x)=4x+7/1,求定义域

问题描述:

f(x)=4x+7/1,求定义域

f(x)=1/(4x+7)定义域为(-无穷大,-7/4)U(-7/4,+无穷大)
f(x)=1/(4x)+7定义域为(-无穷大,0)U(0,+无穷大)
f(x)=(1/4)x+7定义域为(-无穷大,+无穷大)