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Show that if `f_1` and `f_2` are one-one maps from `R` to `R` , then the product `f_1xxf_2: R->R` defined by `(f_1xxf_2)(x)=f_1(x)f_2(x)` need not be one-one.

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As we know that `f_1:R->R`, given by `f_1(x)=x`, and `f_2(x)=x` are one-one.
Now Proof `f_1` is one one :
Find `f_1(x_1):`
`impliesf_1(x_1)=x_1`
Find `f_1(x_2):`
`impliesf_1(x_2)=x_2`
Now let `f_1(x_1)=f_1(x_2)`
`impliesx_1=x_2`
...
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RD SHARMA-FUNCTION-Solved Examples And Exercises
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  8. Show that f: R->R , given by f(x)=x-[x] , is neither one-one nor onto.

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