diff --git a/src/basic/math_trans/poly_sin.s b/src/basic/math_trans/e2ef.poly_sin.s
similarity index 59%
rename from src/basic/math_trans/poly_sin.s
rename to src/basic/math_trans/e2ef.poly_sin.s
index 4b4f466f..4f034b1d 100644
--- a/src/basic/math_trans/poly_sin.s
+++ b/src/basic/math_trans/e2ef.poly_sin.s
@@ -3,7 +3,13 @@
 ;; #LAYOUT# *  BASIC_0  #TAKE
 ;; #LAYOUT# *   *       #IGNORE
 
+; This file is under the MIT license, it contains code released by Microsoft Corporation.
+; See LICENSE for more information.
+
 ; Polynomial for the sine function
+;
+; This is 2 coefficients shorter than SINCON in the Microsoft implementation.
+; See https://www.c64-wiki.com/wiki/SIN
 
 
 !ifdef CONFIG_TRANSCENDENTAL_FUNCTIONS {
@@ -18,12 +24,6 @@ poly_sin:
 	+PUT_CONST_POLY_SIN_3
 	+PUT_CONST_POLY_SIN_4
 	+PUT_CONST_POLY_SIN_5
-	+PUT_CONST_POLY_SIN_6
-
-	
-; Constant 0.75 needed for sine calculation
-sin_three_quarters:
-    !byte $80, $40, $00, $00, $00
-
+    +PUT_CONST_POLY_SIN_6
 
 }
diff --git a/tools/similarity.c b/tools/similarity.c
index b32a2c70..4f24c5eb 100644
--- a/tools/similarity.c
+++ b/tools/similarity.c
@@ -33,7 +33,7 @@ unsigned short microsoft_basic_chunks[NUM_CHUNKS * 2] = {
     0xBDDD, 0xBF51,
     0xBFB4, 0xBFEC,
     0xE264, 0xE26A,
-    0xE30E, 0xE37A,
+    0xE2EF, 0xE37A,
 };