Trigonometry

Option B is correct because, in a standard 30-60-90 right triangle, the sine of 30 degrees is the ratio of the opposite side to the hypotenuse, which is always 1/2. Option D is incorrect because the square root of 3 over 2 is the cosine of 30 degrees, not the sine.

Since a 45-degree angle exists in an isosceles right triangle, the opposite and adjacent sides are equal, making their ratio, which is tangent, equal to 1. Option B is incorrect because 1/2 is not the value of any basic trigonometric function at 45 degrees.

Option B is correct because, in a standard 30-60-90 right triangle, the sine of 30 degrees is the ratio of the opposite side to the hypotenuse, which is always 1/2. A diagram for this topic isn't available yet — the worked example below walks the same reasoning step by step.

• !Option D is incorrect because the square root of 3 over 2 is the cosine of 30 degrees, not the sine.
• !Option C is incorrect because the square root of 3 over 2 is the sine of 60 degrees, not its cosine.
• !Option B is incorrect because 1/2 is not the value of any basic trigonometric function at 45 degrees.

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