Break down angle: Break down the angle 1219π into a sum or difference of angles that are easier to work with, such as π and 4π or 3π and 6π, since the tangent values for 4π, 3π, and 6π are known.1219π can be expressed as 1216π+123π, which simplifies to π0.
Use angle sum identity: Use the angle sum identity for tangent, which states that tan(α+β)=1−tan(α)tan(β)tan(α)+tan(β), where α=34π and β=4π.
Find tangent values: Find the exact values for tan(34π) and tan(4π).tan(34π) is the tangent of an angle in the third quadrant, where tangent is positive. The reference angle for 34π is 3π, and tan(3π)=3. Therefore, tan(34π)=3.tan(4π) is the tangent of an angle in the first quadrant, where tangent is positive, and tan(4π)=1.
Substitute values: Substitute the values into the angle sum identity.tan(1219π)=tan(34π+4π)=(1−tan(34π)tan(4π))(tan(34π)+tan(4π))tan(1219π)=(1−3⋅1)(3+1)
Simplify expression: Simplify the expression.tan(1219π)=1−33+1To rationalize the denominator, multiply the numerator and the denominator by the conjugate of the denominator, which is (1+3).
Rationalize denominator: Perform the multiplication to rationalize the denominator.tan(1219π)=(3+1)×(1+3)/((1−3)×(1+3))tan(1219π)=(3+1)×(1+3)/(1−(3)2)tan(1219π)=(3+1)×(1+3)/(1−3)tan(1219π)=(3+1)×(1+3)/(−2)
Expand and simplify: Expand the numerator and simplify the expression.tan(1219π)=(3⋅1+3⋅3+1⋅1+1⋅3)/(−2)tan(1219π)=(3+3+1+3)/(−2)tan(1219π)=(23+4)/(−2)tan(1219π)=−3−2
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