When geometry says LOL

Geometry Level 2

∏ x = 1 89 cos ⁡ ( 3 x ∘ ) = ? \large \displaystyle \prod_{x={1}}^{{89}} \cos(3x^\circ) = \, ?

Clarification : Angles are measured in degrees.

1 1 0 0 − 1 -1 1 2 \dfrac{1}{\sqrt{2}}

Ashish Menon by Ashish Menon , 20, India

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Ashish Menon
Jul 13, 2016

When written in expanded form, in between an expression cos ⁡ 90 ° \cos{90}^° comes at x = 30 ° x = {30}^° which is 0 0 making the entire product 0 \color{#3D99F6}{\boxed{0}} .

0 Helpful 0 Interesting 0 Brilliant 0 Confused

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...