Skip to main content
Ch. 2 - Graphs of the Trigonometric Functions; Inverse Trigonometric Functions
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Non è quello che usi tu?Cambia libro di testo
Capitolo 2, Problema 51

In Exercises 39–54, find the exact value of each expression, if possible. Do not use a calculator. sin⁻¹ (sin π)

Guida verificata passo dopo passo
1
Recall that the function \(\sin^{-1}(x)\), also known as arcsine, is the inverse of the sine function but its output (range) is restricted to \(\left[-\frac{\pi}{2}, \frac{\pi}{2}\right]\).
Identify the input to the arcsine function: here it is \(\sin \pi\). Since \(\sin \pi = 0\), rewrite the expression as \(\sin^{-1}(0)\).
Now, find the angle \(\theta\) within the range \(\left[-\frac{\pi}{2}, \frac{\pi}{2}\right]\) such that \(\sin \theta = 0\).
Recall that \(\sin \theta = 0\) at \(\theta = 0\), \(\pi\), \(2\pi\), etc., but only \(\theta = 0\) lies within the principal range of arcsine.
Therefore, the exact value of \(\sin^{-1}(\sin \pi)\) is the angle \(\theta = 0\).

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
1m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Inverse Sine Function (sin⁻¹ or arcsin)

The inverse sine function, denoted sin⁻¹ or arcsin, returns the angle whose sine is a given value. Its output is restricted to the principal range of [-π/2, π/2] to ensure it is a proper function. Understanding this range is crucial when evaluating expressions like sin⁻¹(sin θ).
Video consigliato:

Sine Function Periodicity and Symmetry

The sine function is periodic with period 2π, meaning sin(θ) = sin(θ + 2πk) for any integer k. It is also symmetric about the origin (odd function). These properties help simplify expressions and find equivalent angles within the principal range of the inverse sine.
Video consigliato:
Percorso guidato
5:33
Period of Sine and Cosine Functions

Evaluating sin⁻¹(sin θ) for Angles Outside the Principal Range

When θ is outside the principal range of arcsin, sin⁻¹(sin θ) equals the angle within [-π/2, π/2] that has the same sine value as θ. This often involves finding a reference angle or using angle identities to map θ back into the principal range.
Video consigliato:
Percorso guidato
7:28
Evaluate Composite Functions - Values Not on Unit Circle