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If f(x) = -1 +|x-1|, -1 le x le 3 " and ...

If `f(x) = -1 +|x-1|, -1 le x le 3 " and " g(x)=2-|x+1|, -2 le x le 2,` then find `fog(x) " and " gof(x).`

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`f(g(x))= -1+|g(x)-1|,-1le g(x) le 3,-2 le x le 2`
`= -1 +|2-|x+1|-1|,-1le2-|x+1|le3, -2 le x le 2`
`= -1+|1-|x+1||,-1 le2-|x+1| le3,-2 le x le 2`
Now `-1 le 2-|x+1|le 3`
`implies -3 le -|x+1| le 1`
`implies -1 le |x+1|le3`
`implies 0le |x+1|le 3`
` implies -3 le x+1 le 3`
`implies -4 le x le 2 `
Also ` -2 le x le 2`
` :. fog(x) = -1+|1-|x+1||,-2 le x le2`
`g(f(x))=2-|f(x)+1|,-2le f(x) le 2, -1 le x le 3`
`=2-| -1+|x-1|+1|,-2 le-1+|x-1| le 2, -1 le x le 3`
`= 2-|x-1|,-2 le -1 +|x-1| le 2, -1 le x le 3 `
Now `-2 le -1+|x-1| le 2`
`implies -1 le |x-1| le 3`
`implies -3 le x-1 le 3`
`implies -2 le x le 4`
Also `-1 le x le 3`
` :. g(f(x))=2 - |x-1|,-1 le x le 3`
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