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Solve the equation for all real values of x.
sec2x + 2secx = 0

User Cory LaNou
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1 Answer

4 votes

Final answer:

To solve the equation sec2x + 2secx = 0, we can factor out a common term of secx and solve each equation separately. The solutions to the equation are x = 2π/3 + 2πk and x = 4π/3 + 2πk, where k is an integer.

Step-by-step explanation:

To solve the equation sec2x + 2secx = 0, we can first factor out a common term of secx:

secx(secx + 2) = 0

So, either secx = 0 or secx + 2 = 0. We can solve each equation separately:

1. secx = 0:
Since secx is the reciprocal of cosx, the equation secx = 0 means that cosx = 1/0, which is not defined. So, there are no real solutions for this part of the equation.

2. secx + 2 = 0:
Subtracting 2 from both sides, we get secx = -2. Since secx is the reciprocal of cosx, the equation secx = -2 means that cosx = -1/2. We can find the solutions for cosx = -1/2 by referring to the unit circle or using the inverse cosine function.

From the unit circle, we can determine that the solutions are x = 2π/3 + 2πk and x = 4π/3 + 2πk, where k is an integer.

So, the solutions to the equation are x = 2π/3 + 2πk and x = 4π/3 + 2πk, where k is an integer.

User Grotrianster
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5.0k points