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45 Degree Angle Length Calculator

45 Degree Angle Formula:

\[ L = \frac{D}{\cos(45°)} \]

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1. What is the 45 Degree Angle Length Calculation?

The 45 degree angle length calculation determines the length (L) of a diagonal when the horizontal or vertical distance (D) is known in a right-angled isosceles triangle where both non-right angles are 45 degrees.

2. How Does the Calculator Work?

The calculator uses the trigonometric formula:

\[ L = \frac{D}{\cos(45°)} \]

Where:

Explanation: The formula calculates the hypotenuse of a right-angled isosceles triangle where the other two sides are equal (45-45-90 triangle).

3. Practical Applications

Details: This calculation is commonly used in construction, engineering, and design when working with diagonal measurements at 45-degree angles, such as roof framing, stair stringers, or diagonal bracing.

4. Using the Calculator

Tips: Simply enter the horizontal or vertical distance in any units, and the calculator will compute the diagonal length in the same units. The distance must be a positive number.

5. Frequently Asked Questions (FAQ)

Q1: Why is cos(45°) used in this calculation?
A: In a 45-45-90 triangle, the ratio of the adjacent side (D) to the hypotenuse (L) is equal to the cosine of 45 degrees.

Q2: What's the simplified version of this formula?
A: Since cos(45°) = √2/2 ≈ 0.7071, the formula simplifies to L ≈ D × 1.4142.

Q3: Does this work for any right triangle?
A: No, this specific formula only works for 45-45-90 triangles. Other angles require different trigonometric calculations.

Q4: Can I use this for three-dimensional calculations?
A: For 3D space, you would need to use more complex formulas involving multiple angles and distances.

Q5: How accurate is this calculation?
A: The calculation is mathematically precise for perfect 45-degree angles. Real-world accuracy depends on how precisely the angle is measured.

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