Tilde floats above superscript instead of above letter

Question

\begin{equation}
\begin{split}
\Tilde{B_{k}^{ij}} = f(B^{i})_{k} + (1 - \lambda) f(B^{j})_{k} \\
\Tilde{y^{ij}} = \lambda y^{i} + (1 - \lambda) y^{j}
\end{split}
\end{equation}

This is my current equation. Unfortunately, the tilde is not directly placed on the B, but instead floats above the supercript. How to fix this?

Answer 1

Welcome to TeX.SE!

Something like this?

\documentclass{article}
\usepackage{amsmath}

\begin{document}
    \begin{equation}
\begin{split}
\Tilde{B}_{k}^{ij} = f(B^{i})_{k} + (1 - \lambda) f(B^{j})_{k} \\
\Tilde{y}^{ij} = \lambda y^{i} + (1 - \lambda) y^{j}
\end{split}
    \end{equation}
\end{document}

Observe, where are } : \Tilde{B}_{k}^{ij} instead of \Tilde{B_{k}^{ij}}.

BTW, it will be helpful, if you would extend your code fragment to complete small document.