Let the polynomial $p$ be defined by $$p(x) = x^3-2x^2+3x+4.$$ Then $p(2x+1)=$ $x^3$ $+$ $x^2$ $+$ $x$ $+$ ,
Hint: The notation $p(2x+1)$ means "replace $x$ with $2x+1$ in the definition of $p$.