Question

Sin20 sin70 - cos20 cosec70

Answer 1

Step-by-step explanation:

sin 20 sin ( 90-20 ) - cos 20 cosec ( 90-20)

sin 20 cos 20 - cos 20 sec 20

( either your question is wrong or its your answer .......there should be sin 20 sec 20 - cos 20 cosec 20 ......then your answer will be zero )