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 Let the function f:RR be defined by f(x)=2x+sinx for xR. Then f is 

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a
one-to-one and onto
b
one-to-one but not onto
c
onto but not one-to-one
d
neither one-to-one nor onto

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detailed solution

Correct option is A

Given that f(x)=2x+sin⁡x,x∈R or  f′(x)=2+cos⁡x But −1≤cos⁡x≤1 or  1≤2+cos⁡x≤3∴ f′(x)>0∀x∈R Therefore, f(x) is strictly increasing and, hence, one-one.  Also, as x→∞,f(x)→∞ , and x→−∞,f(x)→−∞ . Therefore,  Hence, f(x) is onto.  Thus, f(x) is one-one and onto.


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 Let f(x) be defined on [2,2] and is given by f(x)=1,2x0x1,0x2, then f(|x|) is defined as 


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