<h2>
Answer:</h2>
<h2>
Step-by-step explanation:</h2>
<h3>Find angles</h3>
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<h3>Transform the expression using the sum-to-product formula</h3>
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<h3>Combine like terms</h3>
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<h3>Divide both sides of the equation by the coefficient of variable</h3>
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<h3>Apply zero product property that at least one factor is zero</h3>
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<h2>Cos (8A/2) = 0:</h2>
<h3>Cross out the common factor</h3>
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<h3>Solve the trigonometric equation to find a particular solution</h3>
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<h3>Solve the trigonometric equation to find a general solution</h3>
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<h2>cos(-2A/2) = 0</h2>
<h3>Reduce the fraction</h3>
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<h3>Simplify the expression using the symmetry of trigonometric function</h3>
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<h3>Solve the trigonometric equation to find a particular solution</h3>
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<h3>Solve the trigonometric equation to find a general solution</h3>
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<h3>Find the union of solution sets</h3>
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<h2>A = π/8 + nπ/4 or A = π/2 + nπ, n ∈ Z</h2>
<h3>Find the union of solution sets</h3>
<em>I hope this helps you</em>
<em>:)</em>