Evaluate \( \sin \left(\cos ^{-1}\left(\frac{1}{4}\right)\right) \), giving your answer as an exact value (no decimals)

Solve \( 2 \cos ^{2}(t)-3 \cos (t)+1=0 \) for all solutions. \( t=\square+2 k \pi \); Select an answer Give your answers as exact values in a list separated by commas. \( > \) Next Question

Which points are the same as \( \left(18,19^{\circ}\right) \) ? Check all that apply. \( \begin{array}{ll}\left(-18,-161^{\circ}\right) & \left(-18,199^{\circ}\right) \\ \left(18,-341^{\circ}\right) & \left(18,199^{\circ}\right) \\ \left(-18,-379^{\circ}\right) & \left(18,379^{\circ}\right)\end{array} \)

1. Un triangolo rettangolo con gli angoli acuti di \( 30^{\circ} \) e \( 60^{\circ} \) ha l'ipotenusa lunga 50 m . \( \rightarrow \) Calcola la lunghezza dei cateti. \( \quad[25 \mathrm{~m} ; 43 \mathrm{~m}] \)

Solve \( 8 \cos (4 x)=2 \) for the smallest three positive solutions. Give your answers accurate to at least two decimal places, as a list separated by commas.

Which points are the same as \( \left(18,19^{\circ}\right) \) ? Check all that apply. \( \begin{array}{ll}O\left(-18,-161^{\circ}\right) & \bigcirc\left(-18,199^{\circ}\right) \\ \square\left(18,-341^{\circ}\right) & \bigcirc\left(18,199^{\circ}\right) \\ \left(-18,-379^{\circ}\right) & \left(18,379^{\circ}\right)\end{array} \)