Answer :
sin a / sin a + tan a - 1 + cos a / cosec a + cot a - 1
1 + tan a - 1 + cos a.sin a + cot a - 1
tan a + cos a.sin a + cot a - 1
1 + tan a - 1 + cos a.sin a + cot a - 1
tan a + cos a.sin a + cot a - 1