Question

find the sum of Cos1 +cos2+cos3+..+cos179​

Answer 1

Step-by-step explanation:

Cos 1 + cos 179) + (cos2 + cos 178) + (cos3+ cos177) +… ... If you are finding the sum of all values of cos from 1 to 180 what you are doing is,.

Answer 2

Answer:

Dear student

As cos 179 = cos (180-1) = - cos1

Similarly

Cos 178 = - cos2

Cos 177 = - cos3

Hencw when adding all terms cancelled out.

Only cos90 + cos180 is remaining

Now cos 90 = 0 and cos 180 = - 1

Hence final answer is -1.