You can form 2 equilateral triangles within the shaded region itself and the length of each side is 2r.
Next is to find the total area of these 2 triangles. You can use the equation half x base x height. The base is 2r and the height can be found with pythagoras theorem.
Since we know that there are 2 equilateral triangles, we will know that the angle is 120 degrees. Thus, find the area of the sector now using the formula half x radius squared x theta. The theta is 120 x pi divide 180.
Use this value to minus off the total area of the 2 equilateral triangles found earlier. Name this value x.
The answer can then be proven by the following expression:
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You can form 2 equilateral triangles within the shaded region itself and the length of each side is 2r.
Next is to find the total area of these 2 triangles. You can use the equation half x base x height. The base is 2r and the height can be found with pythagoras theorem.
Since we know that there are 2 equilateral triangles, we will know that the angle is 120 degrees. Thus, find the area of the sector now using the formula half x radius squared x theta. The theta is 120 x pi divide 180.
Use this value to minus off the total area of the 2 equilateral triangles found earlier. Name this value x.
The answer can then be proven by the following expression:
2x + Total Area of the 2 equilateral triangles.
Good luck to you in your Prelims XD
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Well your question is not really that hard. There are question harder than that:P
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can u show scanned working………plus proving.
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good question but too much hard as it seems , by looking at it.
add some more question so that this shall help students.
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