Wednesday

July 30, 2014

July 30, 2014

Posted by **stellar** on Saturday, October 22, 2011 at 12:37am.

2 cos2 θ − cos θ − 1 = 0

- precal -
**Steve**, Saturday, October 22, 2011 at 6:38amwhat's the problem. You know how to solve quadratics:

Let x = cosθ

2x^2 - x - 1 = 0

(2x+1)(x-1) = 0

x = -1/2 or 1

So,

cosθ = -1/2 or 1

. . .

**Related Questions**

precal - Solve the given equation. (Enter your answers as a comma-separated list...

precal - Solve the given equation. (Enter your answers as a comma-separated list...

pre-calc help - Solve the given equation. (Enter your answers as a comma-...

precal - Find all solutions of the given equation. (Enter your answers as a ...

calculus - Solve the given equation. (Enter your answers as a comma-separated ...

precalculus - Solve the given equation. (Enter your answers as a comma-separated...

precalculus - Solve the given equation. (Enter your answers as a comma-separated...

precalculus - Find all solutions of the given equation. (Enter your answers as a...

precalculus - Use a Double- or Half-Angle Formula to solve the equation in the ...

GED MATH - You are given an equation of the form y = ax2 + bx + c. y = 4x2 + 2x...