Math Problem Statement

find the exact value of cos^(2)65(degrees)+sin^(2)65(degrees)

Solution

The expression cos2(65)+sin2(65)\cos^2(65^\circ) + \sin^2(65^\circ) can be simplified using the Pythagorean identity:

cos2(θ)+sin2(θ)=1\cos^2(\theta) + \sin^2(\theta) = 1

This identity holds true for any angle θ\theta. In this case, since θ=65\theta = 65^\circ, we can conclude:

cos2(65)+sin2(65)=1\cos^2(65^\circ) + \sin^2(65^\circ) = 1

So, the exact value is:

11

Would you like further clarification or details on this?

Here are 5 related questions to explore further:

  1. What is the Pythagorean identity in trigonometry?
  2. How can you prove cos2(θ)+sin2(θ)=1\cos^2(\theta) + \sin^2(\theta) = 1 geometrically?
  3. How does the Pythagorean identity apply to non-acute angles?
  4. What are the other trigonometric identities, such as sum and difference formulas?
  5. How do you calculate cos(65)\cos(65^\circ) or sin(65)\sin(65^\circ) using a calculator?

Tip: Always remember that trigonometric identities are fundamental tools for simplifying and solving many types of trigonometric equations.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Trigonometry
Pythagorean Identity

Formulas

cos^2(θ) + sin^2(θ) = 1

Theorems

Pythagorean Identity

Suitable Grade Level

Grades 9-10