I dont know what to do. I graph it on calculator but what do i do next
y=x+ abs x+1 abs
2 Answers
Look Dan, Robert in CA gave you an answer; I hope that helps.
But the stump for you was that your calculator graphed it and you did not understand the steps, right?
the given function was y = x + |x+1|
you should know that if x+1 is >= o, then the function is y = x + (x+1) = 2x+1, but if x+1 < 0 [ x < -1],
then the function is y = x + -(x+i) = -1 or a flat line down there...
That is wat you device did, in milliseconds = graph a flat line to x=-1
and then a rising line with slope 2 after that. Get it? Got it? Good!
I am interpreting yoru question as:
y = x + | x + 1|
The absolute value of a number is either the number or its opposite, whichever is positive.
For x < 0, |x| = -x. For x ≥ 0, |x| = x
Examples:
|-2| = -(-2) = 2
|7| = 7
For your equation, you have |x+1|. When x + 1 < 0, |x+1| = -(x+1) = -x-1. When x+1 ≥ 0, |x+1| = x+1.
x+1 ≥ 0 is the same as saying x ≥ -1.
x + 1 < 0 is the same as saying x < -1
So your equation could be described as two separate equations depending on what the vlaue of x is:
y = x + | x + 1|
For x < -1:
y = x + -(x+1)
or y = -1
For x ≥ -1:
y = x + x +1
or y = 2x + 1
To summarize:
y = -1 {x < -1} and y = 2x + 1 {x ≥ -1}
This is called a piecewise function since it is defined in pieces. All functions with absolute values can be turned into piecewise functions.
This graph should look like a steep upward climbing line to the right of x = -1 and a horizontal line below the y axis to the left of x = -1. At x = -1, the y value is -1 for both halves of the equation, so it is a continuous function.
I'm not sure where the question wants you to go with this since you are not given any y or x values to plug in and use to solve. Perhaps there is more to the problem you can add with the discussion feature.



Comments
What is the problem asking you to solve for?
- Tamara J. 10/16/2012