Practice problem
If sin(x)=18\sin(x)=\frac18sin(x)=81 and xxx is in quadrant I, then find an exact value for cos(2x).\cos(2x).cos(2x).
78\frac{7}{8}87
2932\frac{29}{32}3229
1516\frac{15}{16}1615
3132\frac{31}{32}3231
Type a concept, like “slope” or “photosynthesis”.
