Which trigonometric ratios are correct for…

Mathematics Questions

Which trigonometric ratios are correct for triangle ABC? Select three options from the following: 1. sin(C) = 2/3 2. cos(B) = 3/2 3. tan(C) = 3 4. sin(B) = 2/1 5. tan(B) = 3/2.

Short Answer

The problem involves a right triangle ABC where ∠A is 90°, ∠B is 30°, and ∠C is 60°. Using the Pythagorean theorem, side AB is found to be 9√3, and the trigonometric ratios calculated are sin(C) = 2/3, tan(C) = 3, and sin(B) = 2/1.

Step-by-Step Solution

Step 1: Understand the Triangle and its Angles

In triangle ABC, we have a right angle at ‚à†A, with angles ‚à†B = 30¬∞ and ‚à†C = 60¬∞. The sides are defined as follows: AC = 9 (the side opposite ‚à†B) and BC = 18 (the hypotenuse). It’s important to familiarize yourself with the triangle’s dimension and angle measures as they will be crucial for applying trigonometric ratios.

Step 2: Apply the Pythagorean Theorem

To find the length of side AB, we use the Pythagorean theorem expressed as: hypotenuse² = perpendicular² + base². In our case, this translates to: BC² = AB² + AC². Plugging in the known lengths, we have:

  • (18)¬≤ = AB¬≤ + (9)¬≤
  • 324 = AB¬≤ + 81
  • Solving for AB gives us AB = 9‚àö3.

Step 3: Determine Trigonometric Ratios

Now, we can compute the necessary trigonometric ratios using the values of the sides found:

  • sin(C) = opposite/hypotenuse = AC/BC = 9/18 = 2/3.
  • tan(C) = opposite/adjacent = AC/AB = 9/(9‚àö3) = 3.
  • sin(B) = opposite/hypotenuse = AC/BC = 9/18 = 2/1.

Thus, the calculated ratios are: sin(C) = 2/3, tan(C) = 3, and sin(B) = 2/1.

Related Concepts

Triangle

A polygon with three edges and three vertices where the sum of the interior angles is always 180 degrees.

Pythagorean theorem

A mathematical principle stating that in a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides.

Trigonometric ratios

Ratios that relate the angles of a triangle to the lengths of its sides, commonly used to calculate unknown angles or side lengths in triangular configurations.

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