Troubleshooting Trig Identities and Equations

Thread starter zizkio46
Start date Oct 26, 2008
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Identity Trig

AI Thread Summary

The equation cos²(x) = sin(x) - 1/2 leads to the quadratic equation sin(x) - 0.5 = 1 - sin²(x). The user is struggling to solve this equation and is not getting results that match their calculator. They express confusion over the relationship between the two forms of cos²(x) and the resulting quadratic. The discussion emphasizes the need for proper manipulation of trigonometric identities to solve the equation accurately. Clarifying these identities is crucial for finding the correct solution.

Oct 26, 2008

zizkio46

Homework Statement

cos(squared)x = sinx-1/2

Homework Equations

cos(squared)x= 1-sin(squared)x

The Attempt at a Solution

I tried everything but my answer does not match my answers in calculator

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Oct 26, 2008

jhicks

If cos^2(x) = sin(x)-0.5 and cos^2(x) = 1-sin^2(x), then wouldn't you agree that sin(x)-0.5 = 1-sin^2(x)? That's a quadratic equation.

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