Why the answer is wrong ( SIMPLE TRIGONOMETRIC)

2014 4 2
1 个回答
回答已采纳
更新时间：2014 4 2
55 次查看（30 天）

0 个投票

My code is:
function onex(y)
cos(y)*cos(y)-sin(y)*sin(y)
end
When I insert y=pi/4 The result is:
>> onex(pi/4)
ans =
2.2204e-16
Does anybody has any suggestions? Thank you in advance!

请先登录，再回答此问题。

 采纳的回答

Joseph Cheng
Joseph Cheng 2014-4-2

0 个投票

to try to get zero as you want, you may have to do it in degrees.
x= pi/4*180/pi;
cosd(x)*cosd(x)-sind(x)*sind(x)
will get you your 0. This is because pi is not exactly pi. http://www.mathworks.com/help/matlab/ref/pi.html

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 MATLAB 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by