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# Modulus Function watch

1. I've got two questions that i have done but the answers in the back of the book say i'm wrong:
1. |4-x| < 2

For this I got 8<x<2 which is obviously wrong because x can't be greater than 8 but less than 2. The book says 2<x<6.

my calculations were as follows: -2<4-x<2
-8<-x<-2
8<x<2
I'm sure i've made some stupid mistake somewhere!

2. |2x-3|<|4+x|

For this i got x<-1/3 or x<7

The book says -1<x<7/3

Any help is much appreciated!
2. Question 1

When you subtract 4 from -2 you do not get -8.

When you multiply by a negative number, the direction of the inequality changes.

Question 2

Show some working. The first step is to square both sides.
3. see stupid mistakes! i did it all in class in a rush. i've got it now. thanks!
4. good

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Updated: October 2, 2010
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