Thread: Functions.

Which of the following fuctions has two zeros?

A) f(x)= |x+1|
B) f(x)= |x|+1
C) f(x)= -|x|-1
D) f(x)= -|x|+1

Do I substitute x for 0 to find this or another number?

I like D)

Originally Posted by dnntau

Which of the following fuctions has two zeros?

A) f(x)= |x+1|
B) f(x)= |x|+1
C) f(x)= -|x|-1
D) f(x)= -|x|+1

Do I substitute x for 0 to find this or another number?

The answer is D.Because if you look at the graph it opens down where it intersects the x-axis twice at -1 and 1.Algebrically you consider the absolute value x as positive and you have: -x+1=0 -x=-1 and x=1 And second consideration is when absolute value x is negative and you have:
-(-x)+1=0 x+1=0 x=-1 So you have two zeros of 1 and -1.Please send me note and let me know if you got it.

Yeah I get it now.
Thank you so much.