Find the Exact Value cos(25)

Problem

cos(25^∘)

Solution

1. Identify the task as finding the exact trigonometric value of cos(25^∘)

2. Determine if the angle is a standard angle or a multiple of standard angles (like 30^∘ 45^∘ or 60^∘.

3. Recognize that 25^∘ is not a standard angle and cannot be expressed as a simple sum or difference of standard angles using integers.

4. Conclude that while cos(25^∘) can be expressed using radicals through the triple-angle formula for 75^∘ or other complex methods, it does not have a simplified "exact value" form commonly used in introductory trigonometry.

5. State the value in its simplest exact form, which is the expression itself.

Final Answer

cos(25^∘)=cos(25^∘)

Want more problems? Check here!