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Ch. 2 - Acute Angles and Right Triangles
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161, 9780135440780, 9780136881117, 9780135440827, 9780135924891Non è quello che usi tu?Cambia libro di testo
Capitolo 3, Problema 2.3.58

Use a calculator to determine whether each statement is true or false. A true statement may lead to results that differ in the last decimal place due to rounding error. ½ sin 40° = sin [½ (40°)]

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1
Identify the two expressions given: the left side is \(\frac{1}{2} \sin 40^\circ\) and the right side is \(\sin \left( \frac{1}{2} \times 40^\circ \right)\).
Calculate the value of \(\sin 40^\circ\) using a calculator, then multiply that result by \(\frac{1}{2}\) to find the left side value.
Calculate the value of \(\frac{1}{2} \times 40^\circ = 20^\circ\), then find \(\sin 20^\circ\) using a calculator to get the right side value.
Compare the two results obtained from the left and right sides to see if they are approximately equal, considering possible minor differences due to rounding.
Conclude whether the statement \(\frac{1}{2} \sin 40^\circ = \sin \left( \frac{1}{2} \times 40^\circ \right)\) is true or false based on the comparison.

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