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If 2 cos(A + B) = 2 sin(A - B) = 1, find...

If `2 cos(A + B) = 2 sin(A - B) = 1`, find the values of A and B.

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To solve the problem, we start with the equations given: 1. \( 2 \cos(A + B) = 1 \) 2. \( 2 \sin(A - B) = 1 \) ### Step 1: Simplify the equations From the first equation, we can simplify it as follows: \[ 2 \cos(A + B) = 1 \implies \cos(A + B) = \frac{1}{2} \] From the second equation, we simplify it similarly: \[ 2 \sin(A - B) = 1 \implies \sin(A - B) = \frac{1}{2} \] ### Step 2: Find angles from trigonometric values We know that: - \( \cos(60^\circ) = \frac{1}{2} \) - \( \sin(30^\circ) = \frac{1}{2} \) From this, we can set up our equations based on the angles: 1. \( A + B = 60^\circ \) (from \( \cos(A + B) = \frac{1}{2} \)) 2. \( A - B = 30^\circ \) (from \( \sin(A - B) = \frac{1}{2} \)) ### Step 3: Solve the system of equations Now we have a system of two equations: 1. \( A + B = 60^\circ \) (Equation 1) 2. \( A - B = 30^\circ \) (Equation 2) To solve for \( A \) and \( B \), we can add both equations: \[ (A + B) + (A - B) = 60^\circ + 30^\circ \] This simplifies to: \[ 2A = 90^\circ \implies A = 45^\circ \] Now, substitute \( A = 45^\circ \) back into Equation 1 to find \( B \): \[ 45^\circ + B = 60^\circ \] Solving for \( B \): \[ B = 60^\circ - 45^\circ = 15^\circ \] ### Final Values Thus, the values of \( A \) and \( B \) are: \[ A = 45^\circ, \quad B = 15^\circ \]
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