diff --git a/nbconvert/filters/markdown_mistune.py b/nbconvert/filters/markdown_mistune.py
index abe70883d..280ae86ef 100644
--- a/nbconvert/filters/markdown_mistune.py
+++ b/nbconvert/filters/markdown_mistune.py
@@ -49,7 +49,7 @@ def parse_multiline_math(self, m):
         """Add token to pass through mutiline math."""
         self.tokens.append({
             "type": "multiline_math",
-            "text": m.string
+            "text": m.group(0)
         })
 
 
diff --git a/nbconvert/filters/tests/test_markdown.py b/nbconvert/filters/tests/test_markdown.py
index 76fd8ca7a..a66d018dd 100644
--- a/nbconvert/filters/tests/test_markdown.py
+++ b/nbconvert/filters/tests/test_markdown.py
@@ -137,18 +137,18 @@ def test_markdown2html_math(self):
             "$$a<b&b<lt$$",
             "$$a<b&lt;b>a;a-b<0$$",
             "$$<k'>$$",
-            """$$x
-=
-2$$""",
-            r"""$$
- b_{l_1,l_2,l_3}^{\phi\phi\omega} = -8\, l_1\times l_2 \,l_1\cdot l_2 \int_0^{\chi_*} d\chi \frac{W(\chi,\chi_*)^2}{\chi^2} \int_0^{\chi}d\chi' \frac{W(\chi',\chi)W(\chi',\chi_*)}{{\chi'}^2} \left[
- P_\psi\left(\frac{l_1}{\chi},z(\chi)\right) P_\Psi\left(\frac{l_2}{\chi'},z(\chi')\right)
-- (l_1\leftrightarrow l_2)
-\right]
-$$""",
-            r"""\begin{equation*}
-x = 2 *55* 7
-\end{equation*}""",
+            ("$$x\\n"
+             "=\\n"
+             "2$$"),
+            ("$$\\n"
+             "b =  \\left[\\n"
+             "P\\left(\\right)\\n"
+             "- (l_1\\leftrightarrow l_2\\n)"
+             "\\right]"
+             "$$"),
+             ("\\begin{equation*}\\n"
+              "x = 2 *55* 7"
+              "\\end{equation*}"),
             """$
 \\begin{tabular}{ l c r }
   1 & 2 & 3 \\