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CBSE Class 10 Answered

prove thatCos1 cos2.................cos180=0
Asked by vaibhavkalind | 15 Nov, 2009, 01:28: PM
answered-by-expert Expert Answer

cos1o cos2o.....cos90o............cos180o

= cos1o cos2o.....(0)............cos180o

= 0.

Since cos900 is zero and zero multiplied bu any number gives zero.

Hence Proved.

 

Answered by | 16 Nov, 2009, 09:14: AM

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