Question

The value of cos10.Cos20.Cos30...........Cos900.......Cos1790 is

Answer 1

cos10.cos20.cos30........cos80.cos90......cos900.....cos1790

We know cos90=0

So the product is

cos10.cos20.cos30.......cos80.0.......cos900.....cos1790

=0

Answer 2

Given:

cos10.Cos20.Cos30...........Cos900.......Cos1790

To Find:

Value of the given expression.

Solution:

1) If we consider the given equation we get to know that the the angle taken it the expression are at the difference of 10.

2) so it is very clear that in between we get the angle as 90°.

• cos10.Cos20.Cos30......Cos80.Cos90.Cos100......Cos900.......Cos1790

3) the value of Cos90 is 0 and we all know very well if we multiply any of the term with 0 we get the answer as 0.

cos10.Cos20.Cos30...........Cos900.......Cos1790 = 0