Determine the function $f:R\to R,$ defined by $f\left(x\right)=\left|x\right|+x, \forall x\in R$  is surjective, injective or bijective

Determine the function $f:Q\to R,$ defined by $f\left(x\right)=2^x, \forall x\in Q$  is surjective, injective or bijective

Determine the function $f:R^{+}\to R^{*},$ defined by $f\left(x\right)=\frac{1}{x}, \forall x\in R^{*}$  is surjective, injective or bijective

Determine the function $f:R\to R,$ given by $f\left(x\right)=2x-7, \forall x\in R$  is surjective, injective or bijective.

Determine the function $f:R\to R,$ given by $f\left(x\right)=x^2-3x+4, \forall x\in R$  is surjective, injective or bijective.