Is there an easier way to (I am aware of my poor translation, but am not familiar with english terminology; however, I think you will understand.) "Reduce the following fraction:"
x|x−1|−x+1x2−2|x|+1
besides doing numerous situations with absolute values (in this case, 4 situations);
in this case I'd make:
i.) x−1≥0, x≤0
ii.) x−1≤0, x≥0
iii.) x−1≥0, x≥0
iv.) x−1≤0, x≤0
Then solve each pair's cross-section of the two solutions...
Second thing I'm not certain about are the "≥" and "≤" signs. Do I have to put on both equations in the pair the equal sign "=", or just ">" / "<". If it's not clear, do I have to make every like:
i.) x−1≥0, x≤0
ii.) x−1≤0, x≥0
or
i.) x−1≥0, x<0
ii.) x−1≤0, x>0
Please explain when to put the "≤" and "≥".
EDIT:
Basically, what I wanted to know is, if there is any kind of faster - automated - way of solving the question. The answers you provided matched my opinion and praxis. The thing here is, I know a faster way of solving these, it includes a, so called "table" (with 'null-points', something like RecklessReckoner advised), if someone is interested I'll make a photo of it. It makes solving these totally automated that you don't have to think about the actual problem and/or understand it, that's why I tried to solve these traditionally to understand it - behind the scenes. Once again, thanks for your answers.
Answer
It takes thinking. When you split into cases, generally you have something like |x−a|, which will be x−a if x≥a and a−x if a≥x. If x=a it doesn't matter which direction you use, so generally you use the sign with the one with the equals because you don't want to exclude a potential solution. The point is "do you know it isn't equal-otherwise include the equals. Then you need to check the solutions you find in the original equation because you may have introduced extraneous solutions.
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