For 30°: (1/2)/(1+√(3)/2) = tan 15°

==> 0.267949 = 0.267949

Yes! (at least for 30°)

]]>sin θ / (1 + cos θ) = tan ( θ / 2 )

]]>For example, if you have this problem

#1

When 53 is added to a number, you get 70. What is the number?

The solution would start this way.

Let x be the number.

Therefore, 53 + x = 70

x = 70 - 53 = 17

#2

25 added to the double of a number is 95. What is the number?

Solution:-

Let x be the number.

Therefore, 25 + 2x = 95

2x = 95 - 25 = 70

x = 70/2 = 35

My favourite is the one with the square made up of a slightly smaller square and 4 right-angled triangles.

And thats the only one I remember!

]]>solution I knew was there. Mathsyperson: I'm impressed! And regarding the "i want this angle

so bad"; It is written by me, and have been more than true for the last 72 hours. But not any more...

hihi... it's like a burden has been lifted from my shoulders, and the salvator:

"www.mathisfun.com". You guys rock!]]>

BTW, I recently saw a page with 50+ ways of proving Pythagoras, so isn't maths grand?

]]>Having said that, well done!]]>

Solve a triangle that goes straight to the centre of the circle. It is a right-angled triangle, with two sides of 1m and 0.333m. That angle would be tan-1(0.333/1), then double that angle for the result (by symmetry).

I figure it is 36.8°

(Gustav - are you drawing those yourself, or just adding "I want his angle so bad"? If you are, then Good Drafting!)

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