diff --git a/math.tex b/math.tex
index c68b504..0931a73 100644
--- a/math.tex
+++ b/math.tex
@@ -34,12 +34,16 @@
 \newcommand{\diffTfrac}[2]{\frac{\text{d} #1}{\text{d} #2}}
 \newcommand{\diffTm}[3]{\diffTfrac{^{#1} #2}{#3^{#1}}}
 \newcommand{\diffPfrac}[2]{\frac{\partial #1}{\partial #2}}
-\newcommand{\intgr}[4]{\int_{#1}^{#2} #3 ~\text{d}#4}
-\newcommand{\intgru}[2]{\int #1 ~\text{d}#2}
-\newcommand{\integrinf}[2]{\int_{-\infty}^[\infty #1 \text{\,d}#2}
+\newcommand{\intgr}[4]{\int_{#1}^{#2} #3 ~\text{ d}#4}
+\newcommand{\intgru}[2]{\int #1 ~\text{ d}#2}
+\newcommand{\intgrinf}[2]{\intgr{-\infty}{+\infty}{#1}{#2}}
 
 \newcommand{\sbk}[1]{\left( #1 \right)}
-\newcommand{\sqbk}[1]{\left[ #q ]\right}
+\newcommand{\sqbk}[1]{\left[ #1 \right]}
+\newcommand{\detb}[1]{\det\sqbk{#1}}
+\newcommand{\cosb}[1]{\cos\sbk{#1}}
+\newcommand{\sinb}[1]{\sin\sbk{#1}}
+
 
 \newcommand{\levicivita}[1]{\varepsilon_{#1}}
 \newcommand{\krondelta}[1]{\delta_{#1}}