Im doing functions, and graphing functions. Here is the question:
Find the X intercepts, and Y intercepts of
f(x) 2x^2 - x -1
The Attempt at a Solution
So first finding the X intercepts, the first thing I do, is change it to:
f(x) = 0 so,
2x^2 - x -1 = 0
Now the book takes the above, and changes it to:
(2x+1)(x-1) = 0 (How do you get this <---, from 2x^2 - x -1 = 0 )
Then it goes,
x = -1/2, x = 1
So the X intercepts are (-1/2,0) and (1,0)
Any help would be great!
P.S: Can you work this out on a graphing calculator? Just curious...