PR1 parentheses fix (#380)

source/precalculus/source/04-PR/01.ptx

@@ -116,7 +116,7 @@
 
           <ol marker="A." cols="1">
             <li><p> The minimum value appears to occur near <m> (0, 8) </m>. </p></li>
-            <li><p> The minimum value appears to occur near <m> (-\dfrac {1}{5}, 10) </m>. </p></li>
+            <li><p> The minimum value appears to occur near <m> \left(-\dfrac {1}{5}, 10\right) </m>. </p></li>
             <li><p> The minimum value appears to occur near <m> (2, -4) </m>. </p></li>
             <li><p> There is no minimum value of this function.</p></li>
         </ol>
@@ -134,7 +134,7 @@
 
           <ol marker="A." cols="1">
             <li><p> The maximum value appears to occur near <m> (-2, 44) </m>. </p></li>
-            <li><p> The maximum value appears to occur near <m> (-\dfrac {1}{5}, 10) </m>. </p></li>
+            <li><p> The maximum value appears to occur near <m> \left(-\dfrac {1}{5}, 10\right) </m>. </p></li>
             <li><p> The maximum value appears to occur near <m> (2, -4) </m>. </p></li>
             <li><p> There is no maximum value of this function.</p></li>
         </ol>
@@ -202,7 +202,7 @@
 
   <observation xml:id="standard-form-aos">
     <statement>
-      <p> Just as with the vertex form of a quadratic, we can use the standard form of a quadratic to find the <term>axis of symmetry</term> <idx><h>quadratic function</h><h>axis of symmetry</h></idx> and the <term>vertex</term> <idx><h>quadratic function</h><h>vertex from standard form</h></idx>by using the values of <m>a, b </m>, and <m> c </m>. Given the standard form of a quadratic, the axis of symmetry is the vertical line <m> x=\dfrac {-b}{2a}</m> and the vertex is at the point <m> (\dfrac{-b}{2a},f(\dfrac{-b}{2a}))</m>.
+      <p> Just as with the vertex form of a quadratic, we can use the standard form of a quadratic to find the <term>axis of symmetry</term> <idx><h>quadratic function</h><h>axis of symmetry</h></idx> and the <term>vertex</term> <idx><h>quadratic function</h><h>vertex from standard form</h></idx>by using the values of <m>a, b </m>, and <m> c </m>. Given the standard form of a quadratic, the axis of symmetry is the vertical line <m> x=\dfrac {-b}{2a}</m> and the vertex is at the point <m> \left(\dfrac{-b}{2a},f\left(\dfrac{-b}{2a}\right)\right)</m>.
       </p>
     </statement>
   </observation>
@@ -513,4 +513,4 @@
     <title>Videos</title>
     <p>It would be great to include videos down here, like in the Calculus book!</p>
 </subsection> -->
-</section>
+</section>