User:Zhoujef000

test

1434

xonk Find all functions $f: \mathbb{R} \to \mathbb{R}$ such that\[f(xonkrbo)=xonkrbo\]for all real numbers $x,o,n,k,r,$ and $b.$

Let $A$ be the set of positive real numbers. Determine, with proof, if there exists at least one function $f : A\to A$ such that\[f(x^x)=f(x)^{f(x)}\]for all real $x$ in $A.$

Determine all functions $f:\mathbb{R} \to \mathbb{R}$ such\[f(x+y)=f(y)\]for all real numbers $x$ and $y.$

Find all functions $f:\mathbb{R}\to \mathbb{R}$ such that\[f\left(x+\dfrac{1}{x}\right)+f\left(y+\dfrac{1}{y}\right)+f\left(z+\dfrac{1}{z}\right)=1\]for all real numbers $x,y,z\neq 0.$