diff --git a/src/main/py/trigonometry.py b/src/main/py/trigonometry.py
index cd98d97..ae1aeb8 100644
--- a/src/main/py/trigonometry.py
+++ b/src/main/py/trigonometry.py
@@ -15,4 +15,6 @@ def rad2deg(radNumber):
     return (radNumber * 180) / math.pi
 
 def sin_approx_bhaskara(radNumber):
-    return radNumber
\ No newline at end of file
+    num = 16 * radNumber * (math.pi - radNumber)
+    denom = 5 * math.pow(math.pi, 2) - 4 * radNumber * (math.pi - radNumber)
+    return num/denom
\ No newline at end of file
diff --git a/src/test/py/test_trigonometry.py b/src/test/py/test_trigonometry.py
index b7324ff..8297175 100644
--- a/src/test/py/test_trigonometry.py
+++ b/src/test/py/test_trigonometry.py
@@ -1,5 +1,6 @@
 import unittest
 from src.main.py.trigonometry import *
+import math
 
 
 class MyTestCase(unittest.TestCase):
@@ -39,6 +40,10 @@ class MyTestCase(unittest.TestCase):
     def test_sin_0_should_be_0(self):
         self.assertEqual(sin_approx_bhaskara(0), 0)
 
+    def test_sin_quarter_pi_should_be_point707(self):
+        delta = sin_approx_bhaskara(0.25*math.pi) - 0.707
+        self.assertLess(delta, 0.01)
+
 
 if __name__ == '__main__':
     unittest.main()