*A challenge for people who honestly enjoy mathematics*

I have a question for people who enjoy a bit of complexity out of a simple math problem.

Prove that sin(x)

Question

*A challenge for people who honestly enjoy mathematics*

I have a question for people who enjoy a bit of complexity out of a simple math problem. 

Prove that sin(x)<x<tan(x) in the given range of (0,pi/2) without using calculus (mean-value theorem/studying function behavior/limits etc) - preferably using a method that is accessible to any 7'th-9'th grader.

anonymous · Answer

So far, proving the first part appears to be quite easy. To prove that sin(x) < x we will use some basic geometry and trigonometrical notions.

anonymous · Answer

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