$\"\"$

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In right angle triangle, the angle is $\"\"$ and its side is $\"\"$ .

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Observe the figure $\"\"$ .

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Sum of three angles in a triangle is $\"\"$ .

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$\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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The trigonometric function

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$\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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The trigonometric function

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ , and $\"\"$ .