diff --git a/src/environment.rs b/src/environment.rs
index 112d01f..c90f1a9 100644
--- a/src/environment.rs
+++ b/src/environment.rs
@@ -1132,18 +1132,16 @@ impl<'src> Environment<'src> {
       }),
     );
 
+    let mut consts = Consts::new().unwrap();
+
     env.add_variable(
       "e",
-      Value::Number(BigFloat::from(1.0).exp(
-        config.precision,
-        config.rounding_mode,
-        &mut Consts::new().unwrap(),
-      )),
+      Value::Number(consts.e(config.precision, config.rounding_mode)),
     );
 
     env.add_variable(
       "pi",
-      Value::Number(BigFloat::from_f64(std::f64::consts::PI, config.precision)),
+      Value::Number(consts.pi(config.precision, config.rounding_mode)),
     );
 
     env.add_variable(
diff --git a/tests/integration.rs b/tests/integration.rs
index 474963d..954ad2c 100644
--- a/tests/integration.rs
+++ b/tests/integration.rs
@@ -490,7 +490,7 @@ fn cosecant() -> Result {
   Test::new()?
     .program("println(csc(pi/2))")
     .expected_status(0)
-    .expected_stdout(Contains("1.00000"))
+    .expected_stdout(Exact("1\n"))
     .run()?;
 
   Test::new()?
@@ -511,7 +511,7 @@ fn secant() -> Result {
   Test::new()?
     .program("println(sec(pi/3))")
     .expected_status(0)
-    .expected_stdout(Contains("1.99"))  // ~2.0000...
+    .expected_stdout(Exact("2\n"))  // ~2.0000...
     .run()
 }
 
@@ -829,7 +829,7 @@ fn functions_with_constants() -> Result {
     .argument("53")
     .program("println(arc(pi / 4))")
     .expected_status(0)
-    .expected_stdout(Exact("0.66577375002835384465\n"))
+    .expected_stdout(Exact("0.66577375002835386362\n"))
     .run()?;
 
   Test::new()?
@@ -845,7 +845,7 @@ fn functions_with_constants() -> Result {
     .argument("53")
     .program("println(e(pi))")
     .expected_status(0)
-    .expected_stdout(Exact("23.140692632779266172\n"))
+    .expected_stdout(Exact("23.140692632779269006\n"))
     .run()
 }