Question

I need to justify how a base in a logarithmic function graph is a base. Here are the choices:

The graph of f(x)= log_3 x+c must intersect with the line y= c+1 when x= 3.

The graph of f(x)= log_3 x+c must intersect with the line y= c when x= 3.

The graph of f(x)= log_3 x+c must intersect with the line x= c when y= 3.

The graph of f(x)= log_3 x+c must intersect with the line x= c+1 when y= 3.

Is it B? I'll be honest, I have no idea how to get the answer and the lesson didn't cover this.

Answer 1

you know that
log_3(3)=1

so, log_3(x)+c = 1+c when x=3