Exponential functions

2010013014

Level: 
B
Let f be a function defined by f(x)=(12)xmm, where m is a parameter. Which of the following statements about the function f and the line y=3 is true?
The graph of f and the line have always a common point for all m(3;).
The graph of f and the line have always a common point for m=3.
The graph of f and the line have always a common point for all m(;3).
The graph of f and the line have always a common point for all mR.

2010013015

Level: 
B
Let f be a function defined by f(x)=2x+m+m, where m is a parameter. Which of the following statements about the function f and the line y=3 is true?
The graph of f and the line have always a common point for all m(;3).
The graph of f and the line have always a common point for m=3.
The graph of f and the line have always a common point for all m(3;+).
The graph of f and the line have always a common point for all mR.