why is value of sin 45 degree always equal to 1/sq rt(2)

Question

anonymous · Answer

http://www.intmath.com/blog/how-do-you-find-exact-values-for-the-sine-of-all-angles/6212 visit this website and you will get your answer

zehanz · Answer

You can leave out the "always". It's the same for every other angle: every angle comes with a sine value that is ...always... the value it is. E.g. sin 30 deg = 1/2, last year, now and for many years to come ;)

Otherwise, use @HappySoul's hint!

mathstudent55 · Answer

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The coordinates of point (x, y) must satisfy the equation
x^2 + y^2 = 1
since point (x, y) lies on the unit circle.
Since the anlge is 45 degrees, the triangle is an isoscleles triangle, and x = y, 
so you end up with y^2 + y^2 = 1
2y^2 = 1
y^2 = 1/2
y = 1/sqrt(2)
The sin45 = y/1 = 1/sqrt(2)

bluesea24 · Answer

hey i think now i got it....thanks a lot for those ans :)