How do I find the value of cos 225?

Question

How do I find the value of cos 225?

1 Answer

Impact of this question

64309 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-09-14T09:44:10

It is $- \frac{\sqrt{2}}{2}$ $-sqrt2/2$

Explanation:

It is $cos (225) = cos (180 + 45) = cos 180 \cdot cos 45 - sin 180 \cdot sin 45 = - 1 \cdot \frac{\sqrt{2}}{2} - 0 \cdot \frac{\sqrt{2}}{2} = - \frac{\sqrt{2}}{2}$ $cos(225)=cos(180+45)=cos180*cos45-sin180*sin45=-1*sqrt2/2-0*sqrt2/2=-sqrt2/2$

Science

Math

Humanities

... and beyond

How do I find the value of cos 225?

1 Answer

Explanation:

Related questions

Impact of this question