Demostrar la siguiente identidad: cos2α= cos²α - sen²α

To determine the number of deer in a forest a forest ranger tags 280 and releases them back

Rectangle bcde is similar to rectangle vwxy. what is the length of side vy? a) 1 7 b) 2 7 c) 3 7 d) 4 7

Recall that two angles are complementary if the sum of their measures is? 90°. find the measures of two complementary angles if one angle is twenty dash nine times the other angle.